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"

asp - open dropdownlist by code

Answers (7)