I have a DropDownList for which I am trying to show a div OnSelectedIndexChanged but it says OBJECT REQUIRED.
I a
Hiding on the Client Side with javascript
Using plain old javascript, you can easily hide the same element in this manner:
var myDivElem = document.getElementById("myDiv");
myDivElem.style.display = "none";
Then to show again:
myDivElem.style.display = "";
jQuery makes hiding elements a little simpler if you prefer to use jQuery:
var myDiv = $("#<%=myDiv.ClientID%>");
myDiv.hide();
... and to show:
myDiv.show();