How to assign a string variable to a SelectCommand

Question

I have my two select statements (Str1,Str2) in two string variables. I also have a condition where the appropriate select statement is selected and assigned to another string (res).

This is the select statement that is to be assigned to the SelectCommand property of a SqlDataSource control on my web page.

The code is:

int id =1;
string Str1 = "Select * from table";
string Str2 = "Select * from table where id = "+id;
string res;
if(id == 0)
{
  res=Str2;
}else
{
  res=Str1;
}

My markup looks like:

<asp:gridview.....></aspgridview>
<asp:SqlDataSource ID="ds1" runat="server"
  ConnectionStrings="<%ConnectionStrings.ConnStr%>"
  SelectCommand="<%# res%>">
</asp:SqlDataSource>

How do I assign my string variable res to my SqlDataSource SelectCommand attribute from my codebehind or inline C# code?

Answer 1

You cann set the SelectCommand property from your code-behind, by adding the following statement after the if/else block:

ds1.SelectCommand = res;

Then you can remove the expression from the markup code:

<asp:SqlDataSource ID="ds1" runat="server"
  ConnectionStrings="<%ConnectionStrings.ConnStr%>" />