C# 操作XML文件，用XML文件保存信息
using System;
using System.Collections.Generic;
using System.Text;
using System.Xml;
using System.IO;
namespace ConfigMgrTest
{
public class SystemConfig
{
#region"基本操作函数"
/// <summary>
/// 得到程序工作目录
/// </summary>
/// <returns></returns>
private static string GetWorkDirectory()
{
try
{
return Path.GetDirectoryName(typeof(SystemConfig).Assembly.Location);
}
catch
{
return System.Windows.Forms.Application.StartupPath;
}
}
/// <summary>
/// 判断字符串是否为空串
/// </summary>
/// <param name="szString">目标字符串</param>
/// <returns>true:为空串;false:非空串</returns>
private static bool IsEmptyString(string szString)
{
if (szString == null)
return true;
if (szString.Trim() == string.Empty)
return true;
return false;
}
/// <summary>
/// 创建一个制定根节点名的XML文件
/// </summary>
/// <param name="szFileName">XML文件</param>
/// <param name="szRootName">根节点名</param>
/// <returns>bool</returns>
private static bool CreateXmlFile(string szFileName, string szRootName)
{
if (szFileName == null || szFileName.Trim() == "")
return false;
if (szRootName == null || szRootName.Trim() == "")
return false;
XmlDocument clsXmlDoc = new XmlDocument();
clsXmlDoc.AppendChild(clsXmlDoc.CreateXmlDeclaration("1.0", "GBK", null));
clsXmlDoc.AppendChild(clsXmlDoc.CreateNode(XmlNodeType.Element, szRootName, ""));
try
{
clsXmlDoc.Save(szFileName);
return true;
}
catch
{
return false;
}
}
/// <summary>
/// 从XML文件获取对应的XML文档对象
/// </summary>
/// <param name="szXmlFile">XML文件</param>
/// <returns>XML文档对象</returns>
private static XmlDocument GetXmlDocument(string szXmlFile)
{
if (IsEmptyString(szXmlFile))
return null;
if (!File.Exists(szXmlFile))
return null;
XmlDocument clsXmlDoc = new XmlDocument();
try
{
clsXmlDoc.Load(szXmlFile);
}
catch
{
return null;
}
return clsXmlDoc;
}
/// <summary>
/// 将XML文档对象保存为XML文件
/// </summary>
/// <param name="clsXmlDoc">XML文档对象</param>
/// <param name="szXmlFile">XML文件</param>
/// <returns>bool:保存结果</returns>
private static bool SaveXmlDocument(XmlDocument clsXmlDoc, string szXmlFile)
{
if (clsXmlDoc == null)
return false;
if (IsEmptyString(szXmlFile))
return false;
try
{
if (File.Exists(szXmlFile))
File.Delete(szXmlFile);
}
catch
{
return false;
}
try
{
clsXmlDoc.Save(szXmlFile);
}
catch
{
return false;
}
return true;
}
/// <summary>
/// 获取XPath指向的单一XML节点
/// </summary>
/// <param name="clsRootNode">XPath所在的根节点</param>
/// <param name="szXPath">XPath表达式</param>
/// <returns>XmlNode</returns>
private static XmlNode SelectXmlNode(XmlNode clsRootNode, string szXPath)
{
if (clsRootNode == null || IsEmptyString(szXPath))
return null;
try
{
return clsRootNode.SelectSingleNode(szXPath);
}
catch
{
return null;
}
}
/// <summary>
/// 获取XPath指向的XML节点集
/// </summary>
/// <param name="clsRootNode">XPath所在的根节点</param>
/// <param name="szXPath">XPath表达式</param>
/// <returns>XmlNodeList</returns>
private static XmlNodeList SelectXmlNodes(XmlNode clsRootNode, string szXPath)
{
if (clsRootNode == null || IsEmptyString(szXPath))
return null;
try
{
return clsRootNode.SelectNodes(szXPath);
}
catch
{
return null;
}
}
/// <summary>
/// 创建一个XmlNode并添加到文档
/// </summary>
/// <param name="clsParentNode">父节点</param>
/// <param name="szNodeName">结点名称</param>
/// <returns>XmlNode</returns>
private static XmlNode CreateXmlNode(XmlNode clsParentNode, string szNodeName)
{
try
{
XmlDocument clsXmlDoc = null;
if (clsParentNode.GetType() != typeof(XmlDocument))
clsXmlDoc = clsParentNode.OwnerDocument;
else
clsXmlDoc = clsParentNode as XmlDocument;
XmlNode clsXmlNode = clsXmlDoc.CreateNode(XmlNodeType.Element, szNodeName, string.Empty);
if (clsParentNode.GetType() == typeof(XmlDocument))
{
clsXmlDoc.LastChild.AppendChild(clsXmlNode);
}
else
{
clsParentNode.AppendChild(clsXmlNode);
}
return clsXmlNode;
}
catch
{
return null;
}
}
/// <summary>
/// 设置指定节点中指定属性的值
/// </summary>
/// <param name="parentNode">XML节点</param>
/// <param name="szAttrName">属性名</param>
/// <param name="szAttrValue">属性值</param>
/// <returns>bool</returns>
private static bool SetXmlAttr(XmlNode clsXmlNode, string szAttrName, string szAttrValue)
{
if (clsXmlNode == null)
return false;
if (IsEmptyString(szAttrName))
return false;
if (IsEmptyString(szAttrValue))
szAttrValue = string.Empty;
XmlAttribute clsAttrNode = clsXmlNode.Attributes.GetNamedItem(szAttrName) as XmlAttribute;
if (clsAttrNode == null)
{
XmlDocument clsXmlDoc = clsXmlNode.OwnerDocument;
if (clsXmlDoc == null)
return false;
clsAttrNode = clsXmlDoc.CreateAttribute(szAttrName);
clsXmlNode.Attributes.Append(clsAttrNode);
}
clsAttrNode.Value = szAttrValue;
return true;
}
#endregion
#region"配置文件的读取和写入"
private static string CONFIG_FILE = "SystemConfig.xml";
/// <summary>
/// 读取指定的配置文件中指定Key的值
/// </summary>
/// <param name="szKeyName">读取的Key名称</param>
/// <param name="szDefaultValue">指定的Key不存在时,返回的值</param>
/// <returns>Key值</returns>
public static int GetConfigData(string szKeyName, int nDefaultValue)
{
string szValue = GetConfigData(szKeyName, nDefaultValue.ToString());
try
{
return int.Parse(szValue);
}
catch
{
return nDefaultValue;
}
}
/// <summary>
/// 读取指定的配置文件中指定Key的值
/// </summary>
/// <param name="szKeyName">读取的Key名称</param>
/// <param name="szDefaultValue">指定的Key不存在时,返回的值</param>
/// <returns>Key值</returns>
public static float GetConfigData(string szKeyName, float fDefaultValue)
{
string szValue = GetConfigData(szKeyName, fDefaultValue.ToString());
try
{
return float.Parse(szValue);
}
catch
{
return fDefaultValue;
}
}
/// <summary>
/// 读取指定的配置文件中指定Key的值
/// </summary>
/// <param name="szKeyName">读取的Key名称</param>
/// <param name="szDefaultValue">指定的Key不存在时,返回的值</param>
/// <returns>Key值</returns>
public static bool GetConfigData(string szKeyName, bool bDefaultValue)
{
string szValue = GetConfigData(szKeyName, bDefaultValue.ToString());
try
{
return bool.Parse(szValue);
}
catch
{
return bDefaultValue;
}
}
/// <summary>
/// 读取指定的配置文件中指定Key的值
/// </summary>
/// <param name="szKeyName">读取的Key名称</param>
/// <param name="szDefaultValue">指定的Key不存在时,返回的值</param>
/// <returns>Key值</returns>
public static string GetConfigData(string szKeyName, string szDefaultValue)
{
string szConfigFile = string.Format("{0}\\{1}", GetWorkDirectory(), CONFIG_FILE);
if (!File.Exists(szConfigFile))
{
return szDefaultValue;
}
XmlDocument clsXmlDoc = GetXmlDocument(szConfigFile);
if (clsXmlDoc == null)
return szDefaultValue;
string szXPath = string.Format(".//key[@name='{0}']", szKeyName);
XmlNode clsXmlNode = SelectXmlNode(clsXmlDoc, szXPath);
if (clsXmlNode == null)
{
return szDefaultValue;
}
XmlNode clsValueAttr = clsXmlNode.Attributes.GetNamedItem("value");
if (clsValueAttr == null)
return szDefaultValue;
return clsValueAttr.Value;
}
/// <summary>
/// 保存指定Key的值到指定的配置文件中
/// </summary>
/// <param name="szKeyName">要被修改值的Key名称</param>
/// <param name="szValue">新修改的值</param>
public static bool WriteConfigData(string szKeyName, string szValue)
{
string szConfigFile = string.Format("{0}\\{1}", GetWorkDirectory(), CONFIG_FILE);
if (!File.Exists(szConfigFile))
{
if (!CreateXmlFile(szConfigFile, "SystemConfig"))
return false;
}
XmlDocument clsXmlDoc = GetXmlDocument(szConfigFile);
string szXPath = string.Format(".//key[@name='{0}']", szKeyName);
XmlNode clsXmlNode = SelectXmlNode(clsXmlDoc, szXPath);
if (clsXmlNode == null)
{
clsXmlNode = CreateXmlNode(clsXmlDoc, "key");
}
if (!SetXmlAttr(clsXmlNode, "name", szKeyName))
return false;
if (!SetXmlAttr(clsXmlNode, "value", szValue))
return false;
//
return SaveXmlDocument(clsXmlDoc, szConfigFile);
}
#endregion
}
}
窗口调用
namespace ConfigMgrTest
{
public partial class MainForm : Form
{
public MainForm()
{
InitializeComponent();
}
private void btnSave_Click(object sender, EventArgs e)
{
if (this.txtUserID.Text.Trim().Equals(string.Empty))
{
MessageBox.Show("请输入用户名");
this.txtUserID.Focus();
return;
}
if (this.txtPassword.Text.Trim().Equals(string.Empty))
{
MessageBox.Show("请输入密码");
this.txtPassword.Focus();
return;
}
//保存
SystemConfig.WriteConfigData("UserID", this.txtUserID.Text.Trim());
SystemConfig.WriteConfigData("Password", this.txtPassword.Text.Trim());
this.txtUserID.Text = null;
this.txtPassword.Text = null;
MessageBox.Show("成功保存到配置文件" + Application.StartupPath + "SystemConfig.xml \n点击读取按钮进行读取!");
}
private void btnClose_Click(object sender, EventArgs e)
{
//读取
this.txtUserID.Text = SystemConfig.GetConfigData("UserID", string.Empty);
this.txtPassword.Text = SystemConfig.GetConfigData("Password", string.Empty);
}
}
}