if (BtnTitleSave.Text == "Save")
{
int count = 0;
for (int i = 0; i < ChklistDomain.Items.Count; i++)
{
if (ChklistDomain.Items[i].Selected == true)
count++;
}
if (count == 0)
{
ScriptManager.RegisterStartupScript(this, this.GetType(), "key", "alert(' Atleast select one domain !')", true);
}
else
{
//Your condition here
}
or u can use javascript check below
function doSubmit()
{
var c = document.getElementsByTagName('input');
for( var i = 0; i < c.length; i++ )
{
if( c[i].type.toLowerCase() == 'checkbox' && c[i].checked )
{
return( true );
}
}
return( false );
}
hope this helps u:)