DataGrid pagination usage Summary

Default paging mode:Select "allow pagination"; page size; page navigation settings, which can be the upper/lower mode, or the start mode of the "page navigation" button in the page number format; private void datashow () // bind data
{
String SQL = "server = 127.0.0.1; database = ltp; user id = sa; password = ";
SqlConnection mycon = new SqlConnection (SQL); string selsql = "select * from data ";
SqlDataAdapter da = new SqlDataAdapter (selsql, mycon); DataSet ds = new DataSet ();
Da. Fill (ds, "data"); this. DataGrid1.DataSource = ds. Tables ["data"];
This. DataGrid1.DataBind ();

} RESPONSE event PageIndexChanged () this. Maid = e. NewPageIndex;
Datashow (); Default paging mode for custom navigation controlsCurrent page: this. label1.Text = (this. dataGrid1.CurrentPageIndex + 1 ). toString (); Because CurrentPageIndex starts from 0, the total number of pages must be + 1: this. label2.Text = this. dataGrid1.PageCount. toString (); // the first page of this. dataGrid1.CurrentPageIndex = 0; // previous page if (this. dataGrid1.CurrentPageIndex> 0)
{
This. Maid-= 1;
This. datashow ();
} // Next page
If (this. Maid-1 ))
{
This. Maid + = 1;
This. datashow ();
} // The last page this. Maid-1 and then datashow ();     Custom Data paging-very important! (Improves performance efficiency)Each time this. datashow (); is used to extract all the data, which reduces the efficiency. The correct method is as follows: 1. Select "allow pagination", "allow custom pagination", and page size. 2. Add the navigation button to set the CommandName attribute, previous, next3, code: // record the start index of each page
Int startindex; private void Page_Load (object sender, System. EventArgs e)
{
// Custom button event
This. btnprevious. Click + = new System. EventHandler (this. NavigateToPage );
This. btnnext. Click + = new System. EventHandler (this. NavigateToPage); // or OnCommand = "NavigateToPage" if (! IsPostBack)
{
Startindex = 0; // obtain the number of records of the data source and assign them to the DataGrid1 string constr = "server = 127.0.0.1; database = ltp; user id = sa; password = ";
SqlConnection mycon = new SqlConnection (constr );
Mycon. Open (); string SQL = "Total select count (*) from data ";
SqlCommand com = new SqlCommand (SQL, mycon); SqlDataReader dr = com. ExecuteReader (CommandBehavior. SingleRow );
If (dr. Read ())
This. DataGrid1.VirtualItemCount = (int) dr ["Total"];
Dr. Close ();
Mycon. Close ();

//
This. bindGrid (startindex, "previous ");}
} // Custom button event
Private void NavigateToPage (object sender, System. EventArgs e)
{
String pageinfo = (Button) sender). CommandName;
Switch (pageinfo)
{
Case "previous ":
If (this. DataGrid1.CurrentPageIndex> 0)
{
This. Maid-= 1;

}
Break; case "next ":
If (this. Maid-1 ))
{
This. Maid + = 1;

}
Break;} // get the start Index
Startindex = this. Maid * this. Maid size;
// Rebind
This. bindGrid (startindex, pageinfo );} // Extract the required data records from the data source-method 2 (tables with int numbers)
Private void bindGrid2 (int startindex, string pageinfo)
{
String constr = "server = 127.0.0.1; database = ltp; user id = sa; password = ";
SqlConnection mycon = new SqlConnection (constr );
Mycon. Open (); string SQL = "select top 5 * from data where Sn> =" + startindex + "order by Sn ";
SqlDataAdapter da = new SqlDataAdapter (SQL, mycon); DataSet ds = new DataSet ();
Da. Fill (ds, "data ");
This. DataGrid1.DataSource = ds. Tables ["data"];
This. DataGrid1.DataBind ();

Mycon. Close ();}   // Extract the required data records from the data source-method 1 (sorted by a string column)
Private void bindGrid (int startindex, string pageinfo)
{
String constr = "server = 127.0.0.1; database = ltp; user id = sa; password = ";
SqlConnection mycon = new SqlConnection (constr );
Mycon. Open (); SqlCommand com = new SqlCommand (); switch (pageinfo)
{
Case "previous ":
String SQL = "select top 5 * from data where shareholding name >=@ id order by shareholding name ";
Com = new SqlCommand (SQL, mycon); // com = new SqlCommand ("select top 5 * from data where shareholding name >=@ id order by shareholding name", mycon );

If (startindex = 0)
{
Com. Parameters. Add ("@ id", SqlDbType. NVarChar, 10). Value = "";
}
Else
{
// Start
Com. Parameters. Add ("@ id", SqlDbType. NVarChar, 10). Value = ViewState [(this. DataGrid1.CurrentPageIndex + 1). ToString ()];
// Com. Parameters. Add ("@ id", SqlDbType. NVarChar, 10). Value = this. DataGrid1.Items [0]. Cells [1]. Text;
}
Break; case "next ":
String sql2 = "select top 5 * from data where shareholding Name> @ id order by shareholding name ";
Com = new SqlCommand (sql2, mycon );

// Assign the column value of the last row to the start of the next page.
Com. Parameters. Add ("@ id", SqlDbType. NVarChar, 10). Value = this. DataGrid1.Items [4]. Cells [1]. Text;
Break;
} SqlDataReader dr = com. ExecuteReader ();
This. Maid = dr;
This. DataGrid1.DataBind ();
Dr. Close ();
Mycon. Close (); // obtain the column value of the first row of the current start.
ViewState [(this. Maid + 1). ToString ()] = this. Maid [0]. Cells [1]. Text;
}