asp - open dropdownlist by code

Question

hi can I open a dropdownlist of asp.net by server code? (on asyncPostBack) tanx. sara.

amit · Answer

thanks for sharing this post it help full

sara shats · Answer

I tryed: Page.ClientScript.RegisterStartupScript(This.GetType()   openListElement( + ddlUnder.ClientID + );  True ); and put debugger on the javascript function but it didn't get in. any idea?

Niradhip Chakraborty · Answer

Use the following code in pagebehind where you want to call the function and write the javascript function in to of the page as it is shown below. Page.ClientScript.RegisterStartupScript(this.GetType()   openListElement(this); ; true); // pass the instance of dropdownlist in onclick event % @ Page Language =C# AutoEventWireup =true CodeFile =Reservation.aspx.cs ClientTarget =uplevel Inherits =New_Reservation EnableEventValidation =false %> DOCTYPE html PUBLIC -//W3C//DTD XHTML 1.0 Transitional//EN http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd> html xmlns =http://www.w3.org/1999/xhtml> head id =Head1 runat =server> title > New Page title > script type =text/javascript> function openListElement(elementRef) { elementRef.size = elementRef.options.length; } script > head > body bottommargin =0 topmargin =0 leftmargin =0 rightmargin =0> form id =frmReservation runat =server> table cellpadding =0 cellspacing =0 border =0 width =100%> tr valign =top> td align =right> td > table > form > body>

sara shats · Answer

I'v tried it before but I have to do it on server side only after updating some fields. it's not going to client side after I tryed to put ScriptManager.RegisterStartupScript but it didnt do it (maybe its becose it's AsyncPostBack?)

Niradhip Chakraborty · Answer

Try this: Here I am showing it onmouseover. Select one Item 1 Item 2 Item 3 Item 4 Item 5 Item 6 function openListElement(elementRef) { elementRef.size = elementRef.options.length; } function closeListElement(elementRef) { elementRef.size = 1; } // --> You also can refer the following thread: http://forums.asp.net/p/1118333/1745578.aspx

sara shats · Answer

like mouse click on it.

Niradhip Chakraborty · Answer

What do you mean by opening dropdown list