来到UI层编写了，由于三层的架构体系，所以UI层只需要和BLL层沟通就好。(BLL层和DAL层交互，DAL层与底层数据库交互)，关于DAL层的编码和BLL层编码实现过程，请参考前面的文章。
先来看看最终效果：（这里只能抛砖引玉，小虫我在界面美观上没有仔细用功，这一点大家千万不能也如此不重视，好的编程人员在UI上也要起码的让客户看上去舒服，这一点我做得很不够。所以后面的界面效果望大家能见谅！）
数据库已经切换了（目前只有Access数据库和SqlServer数据库）
实际上就是实现了用户的增删改和按部门查询的功能，加上了一个鸡肋(数据库切换)（对app.config的配置更新还是有了解的必要）。
<实际上是不存在此需求，具体的一个客户端只选择一种固定数据库的。这里仅仅为了测试方便，硬加上的。>
(其他的比如对部门的增删改功能和组合查询等就省略了。)
接下来，看看实现的过程：(首先界面需要的控件如图)
这里说明一下：控件的命名，后续代码看起来明白些。
| 序号 | 控件名[类型名] | 位置 | 备注 |
| 1 | cboAllDepts | 最上面的ComboBox | |
| 2 | bndingNavigator1 |  |
其属性DataSource=sourceUsers |
| 3 | dgvUsers[DataGridView控件] |  |
dgvUsers.DataSource=sourceUsers 请注意：姓名这一列的命名为：colName，因为后续要编码。 |
| 4 | sourceUsers[BindingSource] |  |
非可视化控件(运行时看不见的控件) sourcUsers.Current获取当前的项 |
| 5 |  |
txtName.Tag=”姓名不能为空!” 为了与errorMsg控件配合显示错误用 ComboBox控件的DropDownStyle=DropDownList属性，这样不可能为空。(FormLoad事件) |
|
| 6 |  |
txtNameAdd.Tag=”姓名不能为空！” 为了与errorMsg控件配合显示错误用 |
|
| 7 | errorMsg[ErrorProvider] |  |
用来在指定控件右边显示错误图标和指定的错误信息 SetError方法、GetError方法 |
| 8 | msgHelp[ErrorProvider] |  |
用来显示添加成功的图标！
|
切换后台数据库：
App.config代码
1 xml version="1.0" encoding="utf-8" ?>
2 <configuration>
3 <appSettings>
4 <add key="ProviderType" value="Sql"/>
5 appSettings>
6 <connectionStrings>
7 <add name="DBConnString"
8 connectionString="Data Source=.\sqlexpress;Initial Catalog=testdb;Integrated Security=True"/>
9 connectionStrings>
10 configuration>
11
其实就只需要更改：
操控XML文档可以用System.Xml命名空间的类。这里提供另外一种方法(读写文件替换)
首先建立一个模板AppTemplate.xml，内容如下：
程序运行的时候读取该文件，将%ProviderType%和%DBConnString%替换成合适的内容，然后将该内容保存到App.config中就可以了。
见上图：
1.读取模板 2.替换特别字符串 3.写入到app.config
4.ConfigurationManager.RefreshSection一定不要忘记，它会强制从磁盘重新读取。否则读取的是缓存内容<要重启程序才能生效>。 
注意：程序如果处在调试状态，你要看到效果：对应的config文件是vshost.exe.config，但程序独立运行不调试的时候，代码要换为：.config。
总之要留心这个问题。（调试和独立运行对应的config文件不同。）
正式基于这点，又上网查询了下，有牛人给出了更好的解决方案<见下图方法：ChangeConfiguration()>，
一来会自动解决调试和独立运行的config文件，二来不要模板文件(读写都不需要)。 实现的直接替换。
在运行测试的过程中，发生了一些异常，主要是Access数据库sql语句访问的一些特殊地方。
对比一下：SqlUserProvider.cs中对应的代码：
参考代码：
Form1.cs代码：
View Code
1 using System;
2 using System.Collections.Generic;
3 using System.ComponentModel;
4 using System.Data;
5 using System.Drawing;
6 using System.Text;
7 using System.Windows.Forms;
8 using 抽象工厂模式.BLL;
9 using System.Configuration;
10
11 namespace 抽象工厂模式
12 {
13 public partial class Form1 : Form
14 {
15 public Form1()
16 {
17 InitializeComponent();
18 }
19
20 private void Form1_Load(object sender, EventArgs e)
21 {
22 sourceUsers.DataSource = UserObj.GetUsers();//获得所有的用户
23 cboDepts.ValueMember = "Id"; //comboBox显示的内容实际关联的值(一般是主键值，通过它后台编码)
24 cboDepts.DisplayMember = "Name"; //comboBox显示的内容
25 var depts = DepartmentObj.GetDepartments();//获得所有的部门<用depts遍历来获取数据库获取的集合>
26 cboDepts.DataSource = depts;//depts集合中的每一个元素类型是 DepartmentObj---对应于ComboBox的每一项
27
28 cboDeptAdd.ValueMember = "Id";
29 cboDeptAdd.DisplayMember = "Name";
30 //不推荐这么写：cboDeptAdd.DataSource=DepartmentObj.GetDepartments();因为避免再次后台访问
31 var deptArrays = depts.ToArray(); //将集合depts复制到新数组deptArray中
32 cboDeptAdd.DataSource = deptArrays;
33
34
35 cboAllDepts.ValueMember = "Id";
36 cboAllDepts.DisplayMember = "Name";
37 depts.Insert(0,new DepartmentObj(0,"所有部门",""));//上1：为了下拉能显示<所有部门>，注意这里
38 cboAllDepts.DataSource = depts.ToArray(); //下2：提示<上1和下2这两行代码不能交换>，因为组合框一旦绑定后，不允许再手动更改Items的元素
39 }
40
41 private void btnEdit_Click(object sender, EventArgs e)
42 {
43 if (txtName.Text.Trim() == "")//验证<姓名不能为空>
44 {
45 errorMsg.SetError(txtName, txtName.Tag.ToString());//设置txtName控件显示错误图标(错误字符串)
46 return;
47 }
48 else
49 errorMsg.SetError(txtName, "");//隐藏错误图标
50 var obj = this.sourceUsers.Current as UserObj; //获得当前的用户域对象 UserObj
51 if (obj == null) return;
52 //更新用户的方法
53 UserObj.UpdateUserObj(obj.Id, obj.Name,
54 (cboDepts.SelectedItem as DepartmentObj).Id //找到选择的部门对象的主键
55 );
56 }
57
58 private void btnInsert_Click(object sender, EventArgs e)
59 {
60 if (txtNameAdd.Text.Trim() == "")//验证<姓名不能为空>
61 {
62 errorMsg.SetError(txtNameAdd, txtNameAdd.Tag.ToString());//设置txtNameAdd控件显示错误图标(错误字符串)
63 return;
64 }
65 else
66 errorMsg.SetError(txtNameAdd, "");//隐藏错误图标
67 UserObj.InsertUserObj((int)cboDeptAdd.SelectedValue, txtNameAdd.Text);//添加用户记录的方法
68 msgHelp.SetError(btnInsert, "添加成功");//显示成功图标
69 txtNameAdd.Text = ""; //清空txtNameAdd的文本
70
71 UsersRefresh();//刷新获得最新数据
72
73 }
74
75
76 private void txtNameAdd_TextChanged(object sender, EventArgs e)
77 {
78 if (msgHelp.GetError(btnInsert) != "") msgHelp.SetError(btnInsert, "");
79 }
80
81
82 private void cboAllDepts_SelectedIndexChanged(object sender, EventArgs e)
83 {
84 if (cboAllDepts.SelectedItem != null) UsersRefresh();
85 }
86
87 ///
88 /// 根据所选择部门获得对应的用户列表
89 ///
90 private void UsersRefresh()
91 {
92 int deptId = (int)cboAllDepts.SelectedValue;
93 if (deptId == 0)
94 sourceUsers.DataSource = UserObj.GetUsers(); //显示所有用户
95 else
96 sourceUsers.DataSource = UserObj.GetUsers(deptId);//显示对应部门的用户
97 }
98
99 private void tsbtnDelete_Click(object sender, EventArgs e)
100 {
101 if (MessageBox.Show("是否删除该记录？", "确认", MessageBoxButtons.OKCancel) ==
102 System.Windows.Forms.DialogResult.OK)
103 {
104 var obj = sourceUsers.Current as UserObj;
105 UserObj.DeleteUserObj(obj.Id); //删除该用户
106 UsersRefresh(); //刷新数据
107 }
108 }
109
110 private void tsbtnRefresh_Click(object sender, EventArgs e)
111 {
112 UsersRefresh();
113 }
114
115 private void tsbtnChangeDb_Click(object sender, EventArgs e)
116 {
117 try
118 {
119 Helper.ChangeDbServer();//切换数据库(Access与SqlServer切换)
120 UserObj.ChangeDB();
121 UsersRefresh();
122 }
123 catch (Exception ex)
124 {
125
126 MessageBox.Show(ex.Message);
127 }
128 }
129
130 private void toolStripButton1_Click(object sender, EventArgs e)
131 {
132 Helper.ChangeConfiguration(); //切换数据库(Access与SqlServer切换)
133 UserObj.ChangeDB();
134 UsersRefresh();
135 }
136
137
138 private void dgvUsers_CellMouseClick(object sender, DataGridViewCellMouseEventArgs e)
139 {
140 string tipError = "";
141 var user= dgvUsers.Rows[e.RowIndex].DataBoundItem as UserObj;//获得当前选中的用户对象
142 if (user != null && string.IsNullOrEmpty(user.Name))
143 {
144 tipError = "姓名不能为空！";
145 dgvUsers.Rows[e.RowIndex].Cells["colName"].ErrorText = tipError;
146 }
147 errorMsg.SetError(txtName, tipError);
148 }
149
150
151 }
152 }
Form1.Designer.cs代码如下：
namespace 抽象工厂模式
{
partial class Form1
{
///
/// Required designer variable.
///
private System.ComponentModel.IContainer components = null;
///
/// Clean up any resources being used.
///
/// true if managed resources should be disposed; otherwise, false.
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}
#region Windows Form Designer generated code
///
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
///
private void InitializeComponent()
{
this.components = new System.ComponentModel.Container();
System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(Form1));
this.label1 = new System.Windows.Forms.Label();
this.txtName = new System.Windows.Forms.TextBox();
this.label2 = new System.Windows.Forms.Label();
this.cboDepts = new System.Windows.Forms.ComboBox();
this.btnEdit = new System.Windows.Forms.Button();
this.errorMsg = new System.Windows.Forms.ErrorProvider(this.components);
this.cboDeptAdd = new System.Windows.Forms.ComboBox();
this.txtNameAdd = new System.Windows.Forms.TextBox();
this.btnInsert = new System.Windows.Forms.Button();
this.label3 = new System.Windows.Forms.Label();
this.label4 = new System.Windows.Forms.Label();
this.msgHelp = new System.Windows.Forms.ErrorProvider(this.components);
this.panel1 = new System.Windows.Forms.Panel();
this.panel3 = new System.Windows.Forms.Panel();
this.dgvUsers = new System.Windows.Forms.DataGridView();
this.bindingNavigator1 = new System.Windows.Forms.BindingNavigator(this.components);
this.bindingNavigatorCountItem = new System.Windows.Forms.ToolStripLabel();
this.bindingNavigatorMoveFirstItem = new System.Windows.Forms.ToolStripButton();
this.bindingNavigatorMovePreviousItem = new System.Windows.Forms.ToolStripButton();
this.bindingNavigatorSeparator = new System.Windows.Forms.ToolStripSeparator();
this.bindingNavigatorPositionItem = new System.Windows.Forms.ToolStripTextBox();
this.bindingNavigatorSeparator1 = new System.Windows.Forms.ToolStripSeparator();
this.bindingNavigatorMoveNextItem = new System.Windows.Forms.ToolStripButton();
this.bindingNavigatorMoveLastItem = new System.Windows.Forms.ToolStripButton();
this.bindingNavigatorSeparator2 = new System.Windows.Forms.ToolStripSeparator();
this.tsbtnDelete = new System.Windows.Forms.ToolStripButton();
this.tsbtnRefresh = new System.Windows.Forms.ToolStripButton();
this.tsbtnChangeDb = new System.Windows.Forms.ToolStripButton();
this.panel2 = new System.Windows.Forms.Panel();
this.cboAllDepts = new System.Windows.Forms.ComboBox();
this.label5 = new System.Windows.Forms.Label();
this.toolStripButton1 = new System.Windows.Forms.ToolStripButton();
this.colId = new System.Windows.Forms.DataGridViewTextBoxColumn();
this.colName = new System.Windows.Forms.DataGridViewTextBoxColumn();
this.deptTitleDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
this.sourceUsers = new System.Windows.Forms.BindingSource(this.components);
((System.ComponentModel.ISupportInitialize)(this.errorMsg)).BeginInit();
((System.ComponentModel.ISupportInitialize)(this.msgHelp)).BeginInit();
this.panel1.SuspendLayout();
this.panel3.SuspendLayout();
((System.ComponentModel.ISupportInitialize)(this.dgvUsers)).BeginInit();
((System.ComponentModel.ISupportInitialize)(this.bindingNavigator1)).BeginInit();
this.bindingNavigator1.SuspendLayout();
this.panel2.SuspendLayout();
((System.ComponentModel.ISupportInitialize)(this.sourceUsers)).BeginInit();
this.SuspendLayout();
//
// label1
//
this.label1.AutoSize = true;
this.label1.Location = new System.Drawing.Point(75, 402);
this.label1.Name = "label1";
this.label1.Size = new System.Drawing.Size(41, 12);
this.label1.TabIndex = 2;
this.label1.Text = "姓名：";
//
// txtName
//
this.txtName.DataBindings.Add(new System.Windows.Forms.Binding("Text", this.sourceUsers, "Name", true));
this.errorMsg.SetIconPadding(this.txtName, 5);
this.txtName.Location = new System.Drawing.Point(113, 399);
this.txtName.Name = "txtName";
this.txtName.Size = new System.Drawing.Size(100, 21);
this.txtName.TabIndex = 3;
this.txtName.Tag = "姓名不能为空！";
//
// label2
//
this.label2.AutoSize = true;
this.label2.Location = new System.Drawing.Point(75, 429);
this.label2.Name = "label2";
this.label2.Size = new System.Drawing.Size(41, 12);
this.label2.TabIndex = 4;
this.label2.Text = "部门：";
//
// cboDepts
//
this.cboDepts.DataBindings.Add(new System.Windows.Forms.Binding("Text", this.sourceUsers, "DeptTitle", true));
this.cboDepts.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
this.cboDepts.FormattingEnabled = true;
this.errorMsg.SetIconPadding(this.cboDepts, 5);
this.cboDepts.Location = new System.Drawing.Point(113, 426);
this.cboDepts.Name = "cboDepts";
this.cboDepts.Size = new System.Drawing.Size(100, 20);
this.cboDepts.TabIndex = 6;
this.cboDepts.Tag = "部门不能为空！";
//
// btnEdit
//
this.btnEdit.Location = new System.Drawing.Point(152, 461);
this.btnEdit.Name = "btnEdit";
this.btnEdit.Size = new System.Drawing.Size(61, 23);
this.btnEdit.TabIndex = 7;
this.btnEdit.Text = "修改";
this.btnEdit.UseVisualStyleBackColor = true;
this.btnEdit.Click += new System.EventHandler(this.btnEdit_Click);
//
// errorMsg
//
this.errorMsg.ContainerControl = this;
//
// cboDeptAdd
//
this.cboDeptAdd.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
this.cboDeptAdd.FormattingEnabled = true;
this.errorMsg.SetIconPadding(this.cboDeptAdd, 5);
this.cboDeptAdd.Location = new System.Drawing.Point(304, 426);
this.cboDeptAdd.Name = "cboDeptAdd";
this.cboDeptAdd.Size = new System.Drawing.Size(100, 20);
this.cboDeptAdd.TabIndex = 11;
this.cboDeptAdd.Tag = "部门不能为空！";
//
// txtNameAdd
//
this.errorMsg.SetIconPadding(this.txtNameAdd, 5);
this.txtNameAdd.Location = new System.Drawing.Point(304, 399);
this.txtNameAdd.Name = "txtNameAdd";
this.txtNameAdd.Size = new System.Drawing.Size(100, 21);
this.txtNameAdd.TabIndex = 9;
this.txtNameAdd.Tag = "姓名不能为空！";
this.txtNameAdd.TextChanged += new System.EventHandler(this.txtNameAdd_TextChanged);
//
// btnInsert
//
this.errorMsg.SetIconPadding(this.btnInsert, 5);
this.btnInsert.Location = new System.Drawing.Point(339, 461);
this.btnInsert.Name = "btnInsert";
this.btnInsert.Size = new System.Drawing.Size(65, 26);
this.btnInsert.TabIndex = 12;
this.btnInsert.Text = "添加";
this.btnInsert.UseVisualStyleBackColor = true;
this.btnInsert.Click += new System.EventHandler(this.btnInsert_Click);
//
// label3
//
this.label3.AutoSize = true;
this.label3.Location = new System.Drawing.Point(266, 429);
this.label3.Name = "label3";
this.label3.Size = new System.Drawing.Size(41, 12);
this.label3.TabIndex = 10;
this.label3.Text = "部门：";
//
// label4
//
this.label4.AutoSize = true;
this.label4.Location = new System.Drawing.Point(266, 402);
this.label4.Name = "label4";
this.label4.Size = new System.Drawing.Size(41, 12);
this.label4.TabIndex = 8;
this.label4.Text = "姓名：";
//
// msgHelp
//
this.msgHelp.ContainerControl = this;
this.msgHelp.Icon = ((System.Drawing.Icon)(resources.GetObject("msgHelp.Icon")));
//
// panel1
//
this.panel1.Controls.Add(this.panel3);
this.panel1.Controls.Add(this.panel2);
this.panel1.Dock = System.Windows.Forms.DockStyle.Top;
this.panel1.Location = new System.Drawing.Point(0, 0);
this.panel1.Name = "panel1";
this.panel1.Size = new System.Drawing.Size(613, 368);
this.panel1.TabIndex = 13;
//
// panel3
//
this.panel3.Controls.Add(this.dgvUsers);
this.panel3.Controls.Add(this.bindingNavigator1);
this.panel3.Dock = System.Windows.Forms.DockStyle.Fill;
this.panel3.Location = new System.Drawing.Point(0, 34);
this.panel3.Name = "panel3";
this.panel3.Size = new System.Drawing.Size(613, 334);
this.panel3.TabIndex = 5;
//
// dgvUsers
//
this.dgvUsers.AutoGenerateColumns = false;
this.dgvUsers.ColumnHeadersHeightSizeMode = System.Windows.Forms.DataGridViewColumnHeadersHeightSizeMode.AutoSize;
this.dgvUsers.Columns.AddRange(new System.Windows.Forms.DataGridViewColumn[] {
this.colId,
this.colName,
this.deptTitleDataGridViewTextBoxColumn});
this.dgvUsers.DataSource = this.sourceUsers;
this.dgvUsers.Dock = System.Windows.Forms.DockStyle.Fill;
this.dgvUsers.Location = new System.Drawing.Point(0, 25);
this.dgvUsers.Name = "dgvUsers";
this.dgvUsers.RowTemplate.Height = 23;
this.dgvUsers.Size = new System.Drawing.Size(613, 309);
this.dgvUsers.TabIndex = 4;
this.dgvUsers.CellMouseClick += new System.Windows.Forms.DataGridViewCellMouseEventHandler(this.dgvUsers_CellMouseClick);
//
// bindingNavigator1
//
this.bindingNavigator1.AddNewItem = null;
this.bindingNavigator1.BindingSource = this.sourceUsers;
this.bindingNavigator1.CountItem = this.bindingNavigatorCountItem;
this.bindingNavigator1.DeleteItem = null;
this.bindingNavigator1.Items.AddRange(new System.Windows.Forms.ToolStripItem[] {
this.bindingNavigatorMoveFirstItem,
this.bindingNavigatorMovePreviousItem,
this.bindingNavigatorSeparator,
this.bindingNavigatorPositionItem,
this.bindingNavigatorCountItem,
this.bindingNavigatorSeparator1,
this.bindingNavigatorMoveNextItem,
this.bindingNavigatorMoveLastItem,
this.bindingNavigatorSeparator2,
this.tsbtnDelete,
this.tsbtnRefresh,
this.tsbtnChangeDb,
this.toolStripButton1});
this.bindingNavigator1.Location = new System.Drawing.Point(0, 0);
this.bindingNavigator1.MoveFirstItem = this.bindingNavigatorMoveFirstItem;
this.bindingNavigator1.MoveLastItem = this.bindingNavigatorMoveLastItem;
this.bindingNavigator1.MoveNextItem = this.bindingNavigatorMoveNextItem;
this.bindingNavigator1.MovePreviousItem = this.bindingNavigatorMovePreviousItem;
this.bindingNavigator1.Name = "bindingNavigator1";
this.bindingNavigator1.PositionItem = this.bindingNavigatorPositionItem;
this.bindingNavigator1.Size = new System.Drawing.Size(613, 25);
this.bindingNavigator1.TabIndex = 3;
this.bindingNavigator1.Text = "bindingNavigator1";
//
// bindingNavigatorCountItem
//
this.bindingNavigatorCountItem.Name = "bindingNavigatorCountItem";
this.bindingNavigatorCountItem.Size = new System.Drawing.Size(35, 22);
this.bindingNavigatorCountItem.Text = "/ {0}";
this.bindingNavigatorCountItem.ToolTipText = "总项数";
//
// bindingNavigatorMoveFirstItem
//
this.bindingNavigatorMoveFirstItem.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Image;
this.bindingNavigatorMoveFirstItem.Image = ((System.Drawing.Image)(resources.GetObject("bindingNavigatorMoveFirstItem.Image")));
this.bindingNavigatorMoveFirstItem.Name = "bindingNavigatorMoveFirstItem";
this.bindingNavigatorMoveFirstItem.RightToLeftAutoMirrorImage = true;
this.bindingNavigatorMoveFirstItem.Size = new System.Drawing.Size(23, 22);
this.bindingNavigatorMoveFirstItem.Text = "移到第一条记录";
//
// bindingNavigatorMovePreviousItem
//
this.bindingNavigatorMovePreviousItem.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Image;
this.bindingNavigatorMovePreviousItem.Image = ((System.Drawing.Image)(resources.GetObject("bindingNavigatorMovePreviousItem.Image")));
this.bindingNavigatorMovePreviousItem.Name = "bindingNavigatorMovePreviousItem";
this.bindingNavigatorMovePreviousItem.RightToLeftAutoMirrorImage = true;
this.bindingNavigatorMovePreviousItem.Size = new System.Drawing.Size(23, 22);
this.bindingNavigatorMovePreviousItem.Text = "移到上一条记录";
//
// bindingNavigatorSeparator
//
this.bindingNavigatorSeparator.Name = "bindingNavigatorSeparator";
this.bindingNavigatorSeparator.Size = new System.Drawing.Size(6, 25);
//
// bindingNavigatorPositionItem
//
this.bindingNavigatorPositionItem.AccessibleName = "位置";
this.bindingNavigatorPositionItem.AutoSize = false;
this.bindingNavigatorPositionItem.Name = "bindingNavigatorPositionItem";
this.bindingNavigatorPositionItem.Size = new System.Drawing.Size(50, 21);
this.bindingNavigatorPositionItem.Text = "0";
this.bindingNavigatorPositionItem.ToolTipText = "当前位置";
//
// bindingNavigatorSeparator1
//
this.bindingNavigatorSeparator1.Name = "bindingNavigatorSeparator1";
this.bindingNavigatorSeparator1.Size = new System.Drawing.Size(6, 25);
//
// bindingNavigatorMoveNextItem
//
this.bindingNavigatorMoveNextItem.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Image;
this.bindingNavigatorMoveNextItem.Image = ((System.Drawing.Image)(resources.GetObject("bindingNavigatorMoveNextItem.Image")));
this.bindingNavigatorMoveNextItem.Name = "bindingNavigatorMoveNextItem";
this.bindingNavigatorMoveNextItem.RightToLeftAutoMirrorImage = true;
this.bindingNavigatorMoveNextItem.Size = new System.Drawing.Size(23, 22);
this.bindingNavigatorMoveNextItem.Text = "移到下一条记录";
//
// bindingNavigatorMoveLastItem
//
this.bindingNavigatorMoveLastItem.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Image;
this.bindingNavigatorMoveLastItem.Image = ((System.Drawing.Image)(resources.GetObject("bindingNavigatorMoveLastItem.Image")));
this.bindingNavigatorMoveLastItem.Name = "bindingNavigatorMoveLastItem";
this.bindingNavigatorMoveLastItem.RightToLeftAutoMirrorImage = true;
this.bindingNavigatorMoveLastItem.Size = new System.Drawing.Size(23, 22);
this.bindingNavigatorMoveLastItem.Text = "移到最后一条记录";
//
// bindingNavigatorSeparator2
//
this.bindingNavigatorSeparator2.Name = "bindingNavigatorSeparator2";
this.bindingNavigatorSeparator2.Size = new System.Drawing.Size(6, 25);
//
// tsbtnDelete
//
this.tsbtnDelete.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Image;
this.tsbtnDelete.Image = ((System.Drawing.Image)(resources.GetObject("tsbtnDelete.Image")));
this.tsbtnDelete.ImageTransparentColor = System.Drawing.Color.Magenta;
this.tsbtnDelete.Name = "tsbtnDelete";
this.tsbtnDelete.Size = new System.Drawing.Size(23, 22);
this.tsbtnDelete.Text = "toolStripButton1";
this.tsbtnDelete.ToolTipText = "删除用户";
this.tsbtnDelete.Click += new System.EventHandler(this.tsbtnDelete_Click);
//
// tsbtnRefresh
//
this.tsbtnRefresh.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Image;
this.tsbtnRefresh.Image = ((System.Drawing.Image)(resources.GetObject("tsbtnRefresh.Image")));
this.tsbtnRefresh.ImageTransparentColor = System.Drawing.Color.Magenta;
this.tsbtnRefresh.Name = "tsbtnRefresh";
this.tsbtnRefresh.Size = new System.Drawing.Size(23, 22);
this.tsbtnRefresh.Text = "toolStripButton2";
this.tsbtnRefresh.ToolTipText = "刷新";
this.tsbtnRefresh.Click += new System.EventHandler(this.tsbtnRefresh_Click);
//
// tsbtnChangeDb
//
this.tsbtnChangeDb.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Image;
this.tsbtnChangeDb.Image = ((System.Drawing.Image)(resources.GetObject("tsbtnChangeDb.Image")));
this.tsbtnChangeDb.ImageTransparentColor = System.Drawing.Color.Magenta;
this.tsbtnChangeDb.Name = "tsbtnChangeDb";
this.tsbtnChangeDb.Size = new System.Drawing.Size(23, 22);
this.tsbtnChangeDb.Text = "toolStripButton1";
this.tsbtnChangeDb.ToolTipText = "切换数据库";
this.tsbtnChangeDb.Click += new System.EventHandler(this.tsbtnChangeDb_Click);
//
// panel2
//
this.panel2.Controls.Add(this.cboAllDepts);
this.panel2.Controls.Add(this.label5);
this.panel2.Dock = System.Windows.Forms.DockStyle.Top;
this.panel2.Location = new System.Drawing.Point(0, 0);
this.panel2.Name = "panel2";
this.panel2.Size = new System.Drawing.Size(613, 34);
this.panel2.TabIndex = 4;
//
// cboAllDepts
//
this.cboAllDepts.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
this.cboAllDepts.FormattingEnabled = true;
this.cboAllDepts.Location = new System.Drawing.Point(77, 4);
this.cboAllDepts.Name = "cboAllDepts";
this.cboAllDepts.Size = new System.Drawing.Size(181, 20);
this.cboAllDepts.TabIndex = 1;
this.cboAllDepts.SelectedIndexChanged += new System.EventHandler(this.cboAllDepts_SelectedIndexChanged);
//
// label5
//
this.label5.AutoSize = true;
this.label5.Location = new System.Drawing.Point(7, 9);
this.label5.Name = "label5";
this.label5.Size = new System.Drawing.Size(77, 12);
this.label5.TabIndex = 0;
this.label5.Text = "请选择部门：";
//
// toolStripButton1
//
this.toolStripButton1.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Text;
this.toolStripButton1.Image = ((System.Drawing.Image)(resources.GetObject("toolStripButton1.Image")));
this.toolStripButton1.ImageTransparentColor = System.Drawing.Color.Magenta;
this.toolStripButton1.Name = "toolStripButton1";
this.toolStripButton1.Size = new System.Drawing.Size(69, 22);
this.toolStripButton1.Text = "切换数据库";
this.toolStripButton1.Click += new System.EventHandler(this.toolStripButton1_Click);
//
// colId
//
this.colId.DataPropertyName = "Id";
this.colId.HeaderText = "主键";
this.colId.Name = "colId";
this.colId.ReadOnly = true;
//
// colName
//
this.colName.DataPropertyName = "Name";
this.colName.HeaderText = "姓名";
this.colName.Name = "colName";
//
// deptTitleDataGridViewTextBoxColumn
//
this.deptTitleDataGridViewTextBoxColumn.DataPropertyName = "DeptTitle";
this.deptTitleDataGridViewTextBoxColumn.HeaderText = "部门";
this.deptTitleDataGridViewTextBoxColumn.Name = "deptTitleDataGridViewTextBoxColumn";
this.deptTitleDataGridViewTextBoxColumn.ReadOnly = true;
//
// sourceUsers
//
this.sourceUsers.AllowNew = false;
this.sourceUsers.DataSource = typeof(抽象工厂模式.BLL.UserObj);
//
// Form1
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(613, 549);
this.Controls.Add(this.panel1);
this.Controls.Add(this.btnInsert);
this.Controls.Add(this.cboDeptAdd);
this.Controls.Add(this.label3);
this.Controls.Add(this.txtNameAdd);
this.Controls.Add(this.label4);
this.Controls.Add(this.btnEdit);
this.Controls.Add(this.cboDepts);
this.Controls.Add(this.label2);
this.Controls.Add(this.txtName);
this.Controls.Add(this.label1);
this.Name = "Form1";
this.Text = "测试";
this.Load += new System.EventHandler(this.Form1_Load);
((System.ComponentModel.ISupportInitialize)(this.errorMsg)).EndInit();
((System.ComponentModel.ISupportInitialize)(this.msgHelp)).EndInit();
this.panel1.ResumeLayout(false);
this.panel3.ResumeLayout(false);
this.panel3.PerformLayout();
((System.ComponentModel.ISupportInitialize)(this.dgvUsers)).EndInit();
((System.ComponentModel.ISupportInitialize)(this.bindingNavigator1)).EndInit();
this.bindingNavigator1.ResumeLayout(false);
this.bindingNavigator1.PerformLayout();
this.panel2.ResumeLayout(false);
this.panel2.PerformLayout();
((System.ComponentModel.ISupportInitialize)(this.sourceUsers)).EndInit();
this.ResumeLayout(false);
this.PerformLayout();
}
#endregion
private System.Windows.Forms.BindingSource sourceUsers;
private System.Windows.Forms.Label label1;
private System.Windows.Forms.TextBox txtName;
private System.Windows.Forms.Label label2;
private System.Windows.Forms.ComboBox cboDepts;
private System.Windows.Forms.ErrorProvider errorMsg;
private System.Windows.Forms.Button btnEdit;
private System.Windows.Forms.ComboBox cboDeptAdd;
private System.Windows.Forms.Label label3;
private System.Windows.Forms.TextBox txtNameAdd;
private System.Windows.Forms.Label label4;
private System.Windows.Forms.ErrorProvider msgHelp;
private System.Windows.Forms.Button btnInsert;
private System.Windows.Forms.Panel panel1;
private System.Windows.Forms.BindingNavigator bindingNavigator1;
private System.Windows.Forms.ToolStripLabel bindingNavigatorCountItem;
private System.Windows.Forms.ToolStripButton bindingNavigatorMoveFirstItem;
private System.Windows.Forms.ToolStripButton bindingNavigatorMovePreviousItem;
private System.Windows.Forms.ToolStripSeparator bindingNavigatorSeparator;
private System.Windows.Forms.ToolStripTextBox bindingNavigatorPositionItem;
private System.Windows.Forms.ToolStripSeparator bindingNavigatorSeparator1;
private System.Windows.Forms.ToolStripButton bindingNavigatorMoveNextItem;
private System.Windows.Forms.ToolStripButton bindingNavigatorMoveLastItem;
private System.Windows.Forms.ToolStripSeparator bindingNavigatorSeparator2;
private System.Windows.Forms.ToolStripButton tsbtnDelete;
private System.Windows.Forms.Panel panel2;
private System.Windows.Forms.ComboBox cboAllDepts;
private System.Windows.Forms.Label label5;
private System.Windows.Forms.Panel panel3;
private System.Windows.Forms.DataGridView dgvUsers;
private System.Windows.Forms.ToolStripButton tsbtnRefresh;
private System.Windows.Forms.ToolStripButton tsbtnChangeDb;
private System.Windows.Forms.ToolStripButton toolStripButton1;
private System.Windows.Forms.DataGridViewTextBoxColumn colId;
private System.Windows.Forms.DataGridViewTextBoxColumn colName;
private System.Windows.Forms.DataGridViewTextBoxColumn deptTitleDataGridViewTextBoxColumn;
}
}
Help.cs代码：
View Code
1 using System;
2 using System.Collections.Generic;
3 using System.Text;
4 using System.IO;
5 using System.Configuration;
6 using System.Windows.Forms;
7 using System.Reflection;
8 namespace 抽象工厂模式
9 {
10 class Helper
11 {
12 private static string ProviderType = ConfigurationManager.AppSettings["ProviderType"];
13 private static string DBConnString =
14 ConfigurationManager.ConnectionStrings["DBConnString"].ConnectionString;
15 public static void ChangeDbServer()
16 {
17 SetConfig();
18 //可以采用System.Xml命名空间中的类
19
20 string content = File.ReadAllText(Application.StartupPath + "\\AppTemplate.xml");
21 content = content.Replace("%ProviderType%", ProviderType).Replace("%DBConnString%", DBConnString);
22
23 File.WriteAllText(Application.ExecutablePath + ".config", content);
24 // File.WriteAllText(Application.StartupPath + "\\抽象工厂模式.vshost.exe.config",content);
25
26 //强制刷新，避免重启程序
27 ConfigurationManager.RefreshSection("appSettings");
28 ConfigurationManager.RefreshSection("connectionStrings");
29 }
30
31 private static void SetConfig()
32 {
33 if (ProviderType.ToLower() == "sql")
34 {
35 ProviderType = "Access";
36 DBConnString =
37 @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=F:\netStudy\抽象工厂模式\testdb.mdb";
38 }
39 else
40 {
41 ProviderType = "Sql";
42 DBConnString = @"Data Source=.\sqlexpress;Initial Catalog=testdb;Integrated Security=True";
43 }
44 }
45
46 public static void ChangeConfiguration()
47 {
48
49 SetConfig(); //读取程序集的配置文件
50
51 Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
52
53 //获取appSettings节点
54 AppSettingsSection appSettings = (AppSettingsSection)config.GetSection("appSettings");
55 appSettings.Settings["ProviderType"].Value = ProviderType;
56
57 var connectionSection = (ConnectionStringsSection)config.GetSection("connectionStrings");
58 connectionSection.ConnectionStrings["DBConnString"].ConnectionString = DBConnString;
59 //保存配置文件
60 config.Save();
61
62 //强制刷新，避免重启程序
63 ConfigurationManager.RefreshSection("appSettings");//刷新命名节，在下次检索它时将会从磁盘重新读取
64 ConfigurationManager.RefreshSection("connectionStrings");
65 }
66 }
67 }
AccessUserProvider的代码：
View Code
1 using System;
2 using System.Collections.Generic;
3 using System.Text;
4 using System.Data;
5 using System.Data.OleDb;
6 using 抽象工厂模式.DAL;
7 using 抽象工厂模式.DAL.Entity;
8
9 namespace 抽象工厂模式.DAL.Provider.Access
10 {
11 public class AccessUserProvider:UserProvider
12 {
13
14 public override ListGetUsers()
15 {
16 using (OleDbConnection conn = new OleDbConnection(ConnString))
17 {
18 var dbcmd = conn.CreateCommand();
19 dbcmd.CommandText = "GetUsers";
20 dbcmd.CommandType = CommandType.StoredProcedure;
21 conn.Open();
22 return GetUsersFromReader(dbcmd.ExecuteReader());
23 }
24 }
25
26 public override ListGetUsers(int deptId)
27 {
28 using (OleDbConnection conn = new OleDbConnection(ConnString))
29 {
30 var dbcmd = conn.CreateCommand();
31 dbcmd.CommandText = "GetUsersByDepartmentId";
32 dbcmd.CommandType = CommandType.StoredProcedure;
33 dbcmd.Parameters.Add("@DeptId", OleDbType.Integer).Value = deptId;
34 conn.Open();
35 return GetUsersFromReader(dbcmd.ExecuteReader());
36 }
37 }
38
39 public override User GetUserById(int id)
40 {
41 using (OleDbConnection conn = new OleDbConnection(ConnString))
42 {
43 var dbcmd = conn.CreateCommand();
44 dbcmd.CommandText = "GetUserById";
45 dbcmd.CommandType = CommandType.StoredProcedure;
46 dbcmd.Parameters.Add("@Id", OleDbType.Integer).Value =id ;
47 conn.Open();
48 var reader = dbcmd.ExecuteReader();
49 if (reader.Read()) return GetUserFromReader(reader); else return null;
50 }
51 }
52
53 public override bool DeleteUser(int id)
54 {
55 using (OleDbConnection conn = new OleDbConnection(ConnString))
56 {
57 OleDbCommand cmd = new OleDbCommand(
58 "delete from [user] where Id=" + id, conn);
59 conn.Open();
60 return cmd.ExecuteNonQuery() == 1;
61 }
62 }
63
64 public override int InsertUser(User user)
65 {
66 int result = 0;
67 using (OleDbConnection conn = new OleDbConnection(ConnString))
68 {
69 OleDbCommand cmd = new OleDbCommand(
70 @"insert into [user]([name],deptId) values(@name,@deptid);", conn);
71 cmd.Parameters.Add("@name", OleDbType.VarChar).Value = user.Name; //与下面的一行代码不能颠倒
72 cmd.Parameters.Add("@deptid", OleDbType.Integer).Value = user.DeptId;//access的sql语句参数必须按照顺序匹配
73 conn.Open();
74 var trans = conn.BeginTransaction();//执行数据库事务
75 cmd.Transaction = trans;
76 try
77 {
78
79 bool success = cmd.ExecuteNonQuery() == 1;
80 if (success)
81 {
82 cmd.CommandText = "select max(id) from [user] as newid;"; //由于access不支持多条语句一起执行，只好分多次<两次>执行
83 result = (int)cmd.ExecuteScalar();
84 trans.Commit(); //提交事务
85 }
86 }
87 catch (Exception)
88 {
89 trans.Rollback();//出现异常，回滚事务
90 }
91 }
92 return result;
93 }
94
95 public override bool UpdateUser(User user)
96 {
97 using (OleDbConnection conn = new OleDbConnection(ConnString))
98 {
99 OleDbCommand cmd = new OleDbCommand(
100 "update [user] set [name]=@name,deptId=@deptid where Id=@id" , conn);
101 cmd.Parameters.Add("@name", OleDbType.VarChar).Value = user.Name;
102 cmd.Parameters.Add("@deptid", OleDbType.Integer).Value = user.DeptId;
103 cmd.Parameters.Add("@id", OleDbType.Integer).Value = user.Id;
104 conn.Open();
105 return cmd.ExecuteNonQuery() == 1;
106 }
107 }
108
109 }
110 }