Grid view row updating and deleting - asp.net

Question

I have a grid view with below markup and below datasourse (linq query-stored procedure), I have added delete and update command field, but I do not know what code I have to add until deleting and updating for this grid view works.
<asp:GridView ID="GridViewDocuments_Search" runat="server" AutoGenerateColumns=False Visible="False" onrowcommand="GridViewDocuments_Search_RowCommand"
DataKeyNames="DocID" PageSize="100" >
<Columns>
<asp:TemplateField HeaderText = "Details">
<ItemTemplate>
<asp:Button ID ="btn_Show" Text="Details" runat= "server" CommandName= "Details" CommandArgument='<%#
Container.DataItemIndex%>' />
</ItemTemplate>
</asp:TemplateField>
<asp:HyperLinkField DataNavigateUrlFields="Docid,Transid"
DataNavigateUrlFormatString="~/DocResult.aspx?Docid={0}&TransID={1}"
DataTextField="DocumentNo" HeaderText="Doc" />
<asp:BoundField DataField="title" HeaderText="Title" SortExpression="title" />
<asp:BoundField DataField="transmittal" HeaderText="transmittal" SortExpression="transmittal" />
<asp:BoundField DataField="Docid" HeaderText="Docid" Visible="false" />
<asp:CommandField ShowEditButton="True" />
<asp:CommandField ShowDeleteButton="True" />
</Columns>
</asp:GridView>
protected void btnSearch_Click(object sender, EventArgs e)
{
_DataContext = new EDMSDataContext();
var query = _DataContext.spQuickSearch(txtSearchKeywords.Text);
GridViewDocuments.Visible = false;
GridViewDocuments_Search.Visible = true;
GridViewDocuments_Search.DataSource = query;
GridViewDocuments_Search.DataBind();
}
The stored procedure spQuickSearch is like below:
ALTER proc [dbo].[spQuickSearch]
#Searchtext varchar(50)=null
AS
select DocId,TransId,DocumentNo,Title,TRANSMITTAL
from DocumentSum2
where DocumentNo like '%'+#SearchText + '%'
or Title like '%'+#SearchText + '%'
or TRANSMITTAL like '%'+#SearchText + '%'

Answer 1

You can handle commands like this:
protected void GridViewDocuments_Search_RowCommand(object sender, GridViewCommandEventArgs e)
{
string cmdArg = e.CommandArgument.ToString();
switch (e.CommandName)
{
case "Details":
//TODO: handle your Details command...
break;
case "Delete":
//TODO: handle your Delete command...
break;
}
}
You can add as many commands as you want (CommandName property for control). For example you can add another button and set Delete CommandName like this:
<asp:Button ID ="btn_Delete" Text="Delete" runat= "server" CommandName= "Delete" CommandArgument='<%#
Container.DataItemIndex%>' />
After command is completed you can call DataBind to refresh grid:
GridViewDocuments_Search.DataBind();

Answer 2

check this example
http://www.vkinfotek.com/gridview/gridview-commandfield.html
for detail
http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.commandfield.showeditbutton.aspx