<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title>Maintaining State of CheckBoxes to checked While Paging in a GridView Control</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:GridView runat="server" ID="gvdetails" AllowPaging="true" AllowSorting="true" AutoGenerateColumns="false" onpageindexchanging="gvdetails_PageIndexChanging" PageSize="8" DataKeyNames="UserId">
<RowStyle BackColor="#EFF3FB" />
<FooterStyle BackColor="#507CD1" Font-Bold="True" ForeColor="White" />
<PagerStyle BackColor="#2461BF" ForeColor="White" HorizontalAlign="Center" />
<HeaderStyle BackColor="#507CD1" Font-Bold="True" ForeColor="White" />
<AlternatingRowStyle BackColor="White" />
<Columns>
<asp:TemplateField HeaderText="Select">
<ItemTemplate>
<asp:CheckBox ID="chkSelect" runat="server" />
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="UserId" HeaderText="UserId" />
<asp:BoundField DataField="UserName" HeaderText="UserName" />
<asp:BoundField DataField="LastName" HeaderText="LastName" />
<asp:BoundField DataField="Location" HeaderText="Location" />
</Columns>
</asp:GridView>
</div>
</form>
</body>
</html>
---------------
protected void Page_Load(object sender, EventArgs e)
{
if(!IsPostBack)
{
BindGridData();
}
}
//This method is used to bind the gridview
protected void BindGridData()
{
SqlConnection con = new SqlConnection("Data Source=.;Integrated Security=true;Initial Catalog=MySampleDB");
SqlCommand cmd = new SqlCommand("select * from UserInfo", con);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
gvdetails.DataSource = ds;
gvdetails.DataBind();
}
protected void gvdetails_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
SaveCheckedValues();
gvdetails.PageIndex = e.NewPageIndex;
BindGridData();
PopulateCheckedValues();
}
//This method is used to populate the saved checkbox values
private void PopulateCheckedValues()
{
ArrayList userdetails = (ArrayList)Session["CHECKED_ITEMS"];
if (userdetails != null && userdetails.Count > 0)
{
foreach (GridViewRow gvrow in gvdetails.Rows)
{
int index = (int)gvdetails.DataKeys[gvrow.RowIndex].Value;
if (userdetails.Contains(index))
{
CheckBox myCheckBox = (CheckBox)gvrow.FindControl("chkSelect");
myCheckBox.Checked = true;
}
}
}
}
//This method is used to save the checkedstate of values
private void SaveCheckedValues()
{
ArrayList userdetails = new ArrayList();
int index = -1;
foreach (GridViewRow gvrow in gvdetails.Rows)
{
index = (int)gvdetails.DataKeys[gvrow.RowIndex].Value;
bool result = ((CheckBox)gvrow.FindControl("chkSelect")).Checked;
// Check in the Session
if (Session["CHECKED_ITEMS"] != null)
userdetails = (ArrayList)Session["CHECKED_ITEMS"];
if (result)
{
if (!userdetails.Contains(index))
userdetails.Add(index);
}
else
userdetails.Remove(index);
}
if (userdetails != null && userdetails.Count > 0)
Session["CHECKED_ITEMS"] = userdetails;
}
