hi

in asp.net page three is three radio button and three text box. now  i have to check that if radio button one is selected then textbox1 is required to fill and text box 2 and 3 not required to fill , if radio button 2 selected then text 2 required to fill and text box 3 and 1 not required to fill and same for other 

how i can alert messge and check this on button click

regard

What you do is add this script to your page. Then add OnSubmit="return validate();" to your FORM tag.

		<script language="javascript" type="text/javascript">
			function validate()
			{
				var rdo = document.getElementById('<%=rdoList.ClientID%>');
				var select = -1;
				
				if (rdo[0].checked) { select = 0; }
				if (rdo[1].checked) { select = 1; }
				if (rdo[2].checked) { select = 2; }
			
				switch (select)
				{
					case -1:
						// No selection
						alert('no selection'); return false;
						break;
					case 0:
						// first item selected
						var text1 = document.getElementById('<%=Textbox1.ClientID%>');
						if (text1.value == '') { alert('Textbox 1 cannot be empty!!'); return false; }
					case 1:
						// second item selected
						var text2 = document.getElementById('<%=Textbox2.ClientID%>');
						if (text2.value == '') { alert('Textbox 2 cannot be empty!!'); return false; }
					case 2:
						// third item selected
						var text3 = document.getElementById('<%=Textbox3.ClientID%>');
						if (text3.value == '') { alert('Textbox 3 cannot be empty!!'); return false; }
				}
				
				// if we get here then everything is valid
			}
		</script>