前言:
公司项目开发,上周的任务是做基础数据的管理。在Sharepoint2010里边内嵌asp.net的aspx页,遇到了各种各样奇葩的问题,因为之前对sharepoint只是有一些了解,但是没有设计到具体的编程工作,这一次算是初次接触吧。其中有一部分基础数据数据量很大,大致有十多万,因为是对基础数据的维护,所以还需要对数据进行列表展示,增删改查什么的,大家都知道Asp.net里边的GridView有自带的分页,但是,那个分页对于少量的数据还好,对于这种数十万的数据量而言,这种分页方式简直就是灾难。网上关于GridView高效分页的东西有很多,找了一个自己改了改。用着效果还不错,和大家分享一下。
下边就讲一下具体的实现,首先声明,这个东西是不是我原创的,只是在此基础上进行了修饰和完善。希望能给各位有所启发。
一、前台布局
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|
<
div
>
<
div
id
=
"main"
>
<
div
id
=
"search"
>
<
table
>
<
tr
>
<
td
>
<
asp:Label
ID
=
"lb"
runat
=
"server"
Text
=
"姓名"
></
asp:Label
></
td
>
<
td
>
<
asp:TextBox
ID
=
"SearchName"
runat
=
"server"
></
asp:TextBox
>
</
td
>
<
td
>
<
asp:Button
ID
=
"btnSearch"
runat
=
"server"
Text
=
"查询"
onclick
=
"PagerBtnCommand_OnClick"
CommandName
=
"search"
/>
</
td
>
<
td
>
<
asp:Button
ID
=
"btnReset"
runat
=
"server"
Text
=
"重置"
onclick
=
"btnReset_Click"
/>
</
td
>
</
tr
>
</
table
>
</
div
>
<
div
id
=
"gridView"
>
<
asp:GridView
ID
=
"UserGridView"
runat
=
"server"
AutoGenerateColumns
=
"false"
>
<
Columns
>
<
asp:TemplateField
HeaderText
=
"用户名"
>
<
ItemTemplate
>
<
asp:Label
ID
=
"UserName"
runat
=
"server"
Text='<%#Eval("username") %>'></
asp:Label
>
</
ItemTemplate
>
</
asp:TemplateField
>
<
asp:TemplateField
HeaderText
=
"单位名称"
>
<
ItemTemplate
>
<
asp:Label
ID
=
"DisplayName"
runat
=
"server"
Text='<%#Eval("displayname") %>'></
asp:Label
>
</
ItemTemplate
>
</
asp:TemplateField
>
<
asp:TemplateField
HeaderText
=
"组织编码"
>
<
ItemTemplate
>
<
asp:Label
ID
=
"OrgCode"
runat
=
"server"
Text='<%#Eval("orgcode") %>'></
asp:Label
>
</
ItemTemplate
>
</
asp:TemplateField
>
<
asp:TemplateField
HeaderText
=
"组织名称"
>
<
ItemTemplate
>
<
asp:Label
ID
=
"OrgName"
runat
=
"server"
Text='<%#Eval("orgname") %>'></
asp:Label
>
</
ItemTemplate
>
</
asp:TemplateField
>
</
Columns
>
</
asp:GridView
>
</
div
>
<
div
id
=
"page"
>
<
table
>
<
tr
>
<
td
>
<
asp:Label
ID
=
"lbcurrentpage1"
runat
=
"server"
Text
=
"当前页:"
></
asp:Label
>
<
asp:Label
ID
=
"lbCurrentPage"
runat
=
"server"
Text
=
""
></
asp:Label
>
<
asp:Label
ID
=
"lbFenGe"
runat
=
"server"
Text
=
"/"
></
asp:Label
>
<
asp:Label
ID
=
"lbPageCount"
runat
=
"server"
Text
=
""
></
asp:Label
>
</
td
>
<
td
>
<
asp:Label
ID
=
"recordscount"
runat
=
"server"
Text
=
"总条数:"
></
asp:Label
>
<
asp:Label
ID
=
"lbRecordCount"
runat
=
"server"
Text
=
""
></
asp:Label
>
</
td
>
<
td
>
<
asp:Button
ID
=
"Fistpage"
runat
=
"server"
CommandName
=
""
Text
=
"首页"
OnClick
=
"PagerBtnCommand_OnClick"
/>
<
asp:Button
ID
=
"Prevpage"
runat
=
"server"
CommandName
=
"prev"
Text
=
"上一页"
OnClick
=
"PagerBtnCommand_OnClick"
/>
<
asp:Button
ID
=
"Nextpage"
runat
=
"server"
CommandName
=
"next"
Text
=
"下一页"
OnClick
=
"PagerBtnCommand_OnClick"
/>
<
asp:Button
ID
=
"Lastpage"
runat
=
"server"
CommandName
=
"last"
Text
=
"尾页"
key
=
"last"
OnClick
=
"PagerBtnCommand_OnClick"
/>
</
td
>
<
td
>
<
asp:Label
ID
=
"lbjumppage"
runat
=
"server"
Text
=
"跳转到第"
></
asp:Label
>
<
asp:TextBox
ID
=
"GotoPage"
runat
=
"server"
Width
=
"25px"
></
asp:TextBox
>
<
asp:Label
ID
=
"lbye"
runat
=
"server"
Text
=
"页"
></
asp:Label
>
<
asp:Button
ID
=
"Jump"
runat
=
"server"
Text
=
"跳转"
CommandName
=
"jump"
OnClick
=
"PagerBtnCommand_OnClick"
/>
</
td
>
</
tr
>
</
table
>
</
div
>
</
div
>
</
div
>
|
布局的效果如下:
二、后台的代码实现
我会一点一点向大家讲解清楚,这个分页的原理
Members:这里主要定义几个全局的变量,主要用来记录信息的数量、页的数量和当前页
#region Members
const
int
PAGESIZE = 10;
//每页显示信息数量
int
PagesCount, RecordsCount;
//记录总页数和信息总条数
int
CurrentPage, Pages, JumpPage;
//当前页,信息总页数(用来控制按钮失效),跳转页码
const
string
COUNT_SQL =
"select count(*) from p_user"
;
#endregion
|
Methods:
1、GetRecordsCount:该方法主要用来获取当前信息的总数,有一个sqlSearch参数,默认的为default,即初始化页面时,查询所有信息的总条数,当用户输入要搜索的用户名进行检索时,获取符合用户检索条件的信息的总条数
/// <summary>
/// 获取信息总数
/// </summary>
/// <param name="sqlSearch"></param>
/// <returns></returns>
public
static
int
GetRecordsCount(
string
sqlRecordsCount)
{
string
sqlQuery;
if
(sqlRecordsCount ==
"default"
)
{
sqlQuery = COUNT_SQL;
}
else
{
sqlQuery = sqlRecordsCount;
}
int
RecordCount = 0;
SqlCommand cmd =
new
SqlCommand(sqlQuery, Conn());
RecordCount = Convert.ToInt32(cmd.ExecuteScalar());
cmd.Connection.Close();
return
RecordCount;
}
|
2、OverPage:该方法主要用来计算剩余页,当前设置的为每页显示10条数据,如何符合条件的数据有11条,则要显示2页
/// <summary>
/// 计算余页
/// </summary>
/// <returns></returns>
public
int
OverPage()
{
int
pages = 0;
if
(RecordsCount % PAGESIZE != 0)
pages = 1;
else
pages = 0;
return
pages;
}
|
3、ModPage:该方法也是用计算余页,主要用来防止SQL执行溢出
/// <summary>
/// 计算余页,防止SQL语句执行时溢出查询范围
/// </summary>
/// <returns></returns>
public
int
ModPage()
{
int
pages = 0;
if
(RecordsCount % PAGESIZE == 0 && RecordsCount != 0)
pages = 1;
else
pages = 0;
return
pages;
}
|
4、Conn:该方法用来创建数据连接对象,在使用的时候只需改成自己的数据库名即可
/// <summary>
/// 数据连接对象
/// </summary>
/// <returns></returns>
public
static
SqlConnection Conn()
{
SqlConnection conn =
new
SqlConnection(
"data source=.;initial catalog=DB_GSL_ZCW;Integrated Security=true"
);
conn.Open();
return
conn;
}
|
5、GridViewDataBind:该方法主要用来数据绑定,如果传入的参数为default则,默认的绑定所有的数据,否则,则绑定过滤过的数据
/// <summary>
/// GridView数据绑定,根据传入参数的不同,进行不同方式的查询,
/// </summary>
/// <param name="sqlSearch"></param>
private
void
GridViewDataBind(
string
sqlSearch)
{
CurrentPage = (
int
)ViewState[
"PageIndex"
];
//从ViewState中读取页码值保存到CurrentPage变量中进行按钮失效运算
Pages = (
int
)ViewState[
"PagesCount"
];
//从ViewState中读取总页参数进行按钮失效运算
//判断四个按钮(首页、上一页、下一页、尾页)状态
if
(CurrentPage + 1 > 1)
//当前页是否为首页
{
Fistpage.Enabled =
true
;
Prevpage.Enabled =
true
;
}
else
{
Fistpage.Enabled =
false
;
Prevpage.Enabled =
false
;
}
if
(CurrentPage == Pages)
//当前页是否为尾页
{
Nextpage.Enabled =
false
;
Lastpage.Enabled =
false
;
}
else
{
Nextpage.Enabled =
true
;
Lastpage.Enabled =
true
;
}
DataSet ds =
new
DataSet();
string
sqlResult;
//根据传入参数sqlSearch进行判断,如果为default则为默认的分页查询,否则为添加了过滤条件的分页查询
if
(sqlSearch ==
"default"
)
{
sqlResult =
"Select Top "
+ PAGESIZE +
"user_serialid,username,displayname,orgcode,orgname from p_user where user_serialid not in(select top "
+ PAGESIZE * CurrentPage +
" user_serialid from p_user order by user_serialid asc) order by user_serialid asc"
;
}
else
{
sqlResult = sqlSearch;
}
SqlDataAdapter sqlAdapter =
new
SqlDataAdapter(sqlResult, Conn());
sqlAdapter.Fill(ds,
"Result"
);
UserGridView.DataSource = ds.Tables[
"Result"
].DefaultView;
UserGridView.DataBind();
//显示Label控件lbCurrentPaget和文本框控件GotoPage状态
lbCurrentPage.Text = (CurrentPage + 1).ToString();
GotoPage.Text = (CurrentPage + 1).ToString();
sqlAdapter.Dispose();
}
|
6、Page_Load:页面加载函数,主要是在首次进入页面时,进行初始化,默认的获取所有的信息
protected
void
Page_Load(
object
sender, EventArgs e)
{
if
(!IsPostBack)
//首次进行该页时,页面初始化
{
RecordsCount = GetRecordsCount(
"default"
);
//默认信息总数
PagesCount = RecordsCount / PAGESIZE + OverPage();
//默认的页总数
ViewState[
"PagesCount"
] = RecordsCount / PAGESIZE - ModPage();
//保存末页索引,比页总数小1
ViewState[
"PageIndex"
] = 0;
//保存页面初始索引从0开始
ViewState[
"JumpPages"
] = PagesCount;
//保存页总数,跳页时判断用户输入数是否超出页码范围
//显示lbPageCount、lbRecordCount的状态
lbPageCount.Text = PagesCount.ToString();
lbRecordCount.Text = RecordsCount.ToString();
//判断跳页文本框失效
if
(RecordsCount <= 10)
{
GotoPage.Enabled =
false
;
}
GridViewDataBind(
"default"
);
//调用数据绑定函数TDataBind()进行数据绑定运算
}
}
|
7、PagerBtnCommand_OnClick:该方法主要用来处理设计视图页的“首页”、“下一页”,“上一页”,“尾页”,“查询”按钮的Click事件,主要通过不同按钮的CommandName属性来分别处理,需要在前台为每一个按钮相应的CommandName属性赋值,如果用户点击的是“查询”按钮,这个时候需要对查询的Sql语句进行重写,加入过滤条件,即用户输入的查询的条件
/// <summary>
/// 页面按钮Click处理
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
protected
void
PagerBtnCommand_OnClick(
object
sender, EventArgs e)
{
CurrentPage = (
int
)ViewState[
"PageIndex"
];
//从ViewState中读取页码值保存到CurrentPage变量中进行参数运算
Pages = (
int
)ViewState[
"PagesCount"
];
//从ViewState中读取总页参数运算
Button btn = sender
as
Button;
string
sqlResult=
"default"
;
if
(btn !=
null
)
{
string
cmd = btn.CommandName;
switch
(cmd)
//根据不同的CommandName做出不同的处理
{
case
"next"
:
CurrentPage++;
break
;
case
"prev"
:
CurrentPage--;
break
;
case
"last"
:
CurrentPage = Pages;
break
;
case
"search"
:
if
(!
string
.IsNullOrEmpty(SearchName.Text))
{
RecordsCount = GetRecordsCount(
"select count(*) from p_user where username like '"
+ SearchName.Text +
"%'"
);
//获取过滤后的总记录数
PagesCount = RecordsCount / PAGESIZE + OverPage();
//该变量为页总数
ViewState[
"PagesCount"
] = RecordsCount / PAGESIZE - ModPage();
//该变量为末页索引,比页总数小1
ViewState[
"PageIndex"
] = 0;
//保存一个为0的页面索引值到ViewState,页面索引从0开始
ViewState[
"JumpPages"
] = PagesCount;
//保存PageCount到ViewState,跳页时判断用户输入数是否超出页码范围
//显示lbPageCount、lbRecordCount的状态
lbPageCount.Text = PagesCount.ToString();
lbRecordCount.Text = RecordsCount.ToString();
//判断跳页文本框失效
if
(RecordsCount <= 10)
GotoPage.Enabled =
false
;
sqlResult =
"Select Top "
+ PAGESIZE +
"user_serialid,username,displayname,orgcode,orgname from p_user where user_serialid not in(select top "
+ PAGESIZE * CurrentPage +
" user_serialid from p_user order by user_serialid asc) and username like '"
+ SearchName.Text +
"%' order by user_serialid asc"
;
}
else
{
Response.Write(
"请输入您所要查找的用户姓名!"
);
}
break
;
case
"jump"
:
JumpPage = (
int
)ViewState[
"JumpPages"
];
//从ViewState中读取可用页数值保存到JumpPage变量中
//判断用户输入值是否超过可用页数范围值
if
(Int32.Parse(GotoPage.Text) > JumpPage || Int32.Parse(GotoPage.Text) <= 0)
Response.Write(
"<script>alert('页码范围越界!')</script>"
);
else
{
int
InputPage = Int32.Parse(GotoPage.Text.ToString()) - 1;
//转换用户输入值保存在int型InputPage变量中
ViewState[
"PageIndex"
] = InputPage;
CurrentPage = InputPage;
//写入InputPage值到ViewState["PageIndex"]中
sqlResult =
"Select Top "
+ PAGESIZE +
"user_serialid,username,displayname,orgcode,orgname from p_user where user_serialid not in(select top "
+ PAGESIZE * CurrentPage +
" user_serialid from p_user order by user_serialid asc) and username like '"
+ SearchName.Text +
"%' order by user_serialid asc"
;
}
break
;
default
:
CurrentPage = 0;
break
;
}
ViewState[
"PageIndex"
] = CurrentPage;
//将运算后的CurrentPage变量再次保存至ViewState
GridViewDataBind(sqlResult);
//调用数据绑定函数TDataBind()
}
}
|
8、btn_Reset_Click:该方法主要用来进行重置,用户完成一次查询之后,需要重置,才能进行下一次的查询操作
protected
void
btnReset_Click(
object
sender, EventArgs e)
(
RecordsCount = GetRecordsCount(
"default"
);
//默认信息总数
PagesCount = RecordsCount / PAGESIZE + OverPage();
//默认的页总数
ViewState[
"PagesCount"
] = RecordsCount / PAGESIZE - ModPage();
//保存末页索引,比页总数小1
ViewState[
"PageIndex"
] = 0;
//保存页面初始索引从0开始
ViewState[
"JumpPages"
] = PagesCount;
//保存页总数,跳页时判断用户输入数是否超出页码范围
//显示lbPageCount、lbRecordCount的状态
lbPageCount.Text = PagesCount.ToString();
lbRecordCount.Text = RecordsCount.ToString();
//判断跳页文本框失效
if
(RecordsCount <= 10)
{
GotoPage.Enabled =
false
;
}
GridViewDataBind(
"default"
);
//调用数据绑定函数TDataBind()进行数据绑定运算
}
|
这里的高效分页方法主要用的是select top 10 Id ,Name from tb where Id not in (select top 10*N from tb order by Id asc) order by Id asc
示例中的N代表的是页数,之前原子里也有很多关于高效分页的讨论,这里就不再多说了,我个人觉得这个分页语句效果还不错,当然除此之外还有row_number()函数分页、select Max() 分页等等方法,之前也有总结过,有兴趣的朋友可以看一下我之前写的ListView和Repeater高效分页这篇文章,里边讲述的也很详细,只要你一步一步的照着去操练应该问题不大的。
这里需要解释一下的是为什么没有有数据绑定控件直接进行绑定,因为在sharepoint2010项目里边它支持的数据源控件只有XMLDataSource,所以就只有自己动手实现了。
好了今天就到这里了,希望能给大家带来些帮助吧!还请多多指教!