Clentside and server side programing in a button click

In that case you have to write the script like below
Onclientclick="return Validate()";
function Validate()
{
if (document.getelementbyid(txtbox).value=='')
return false;
else
return true;
}

Theresa16y ago

hi
i want to keep the flow of control in the page itself. if textbox is null alert should come and allow to enter value in the teaxtbox .

Manikavelu Velayutham16y ago

You have to call the javascript in the OnClientClick event of the Button.
That javascript function should return false, if the condition not satisfied else return true, that will go to server side function.
Eg:-

"Button1"
       usesubmitbehavior="true"
       text="Open Web site"
       onclientclick="Navigate()"
       runat="server" onclick="Button1_Click" />

function Navigate()
      {
        javascript:window.open("http://www.microsoft.com");
      }