access list using java script and application page for sp2010

Question

I have create an application page for a sit as follows and use java script to access the lists.

<asp:Content ID="PageHead" ContentPlaceHolderID="PlaceHolderAdditionalPageHead" runat="server">

<script type = "text/ecmascript" src ="/hr/_layouts/Jquery/jquery-1.7.1.min.js"  />
<script type ="text/ecmascript"  src ="/hr/_layouts/SP.js"  />

<script language="ecmascript" type ="text/ecmascript">
    var txtCtx;
    var myweb;
    var mylist;

    function getdata() {
        alert("hello");


        txtCtx = SP.ClientContext.get_current();
        myweb = txtCtx.get_web();
        mylist = myweb.get_lists();      
      
       
       
    }


</script>

</asp:Content>

<asp:Content ID="Main" ContentPlaceHolderID="PlaceHolderMain" runat="server">
<ul id ="ulv"></ul>
<div id ="Divlv"></div>
<input type ="button" runat ="server" name ="test"  onclick ="getdata()"  title="click" />
</asp:Content>

<asp:Content ID="PageTitle" ContentPlaceHolderID="PlaceHolderPageTitle" runat="server">
Application Page

</asp:Content>

<asp:Content ID="PageTitleInTitleArea" ContentPlaceHolderID="PlaceHolderPageTitleInTitleArea" runat="server" >
My Application Page
<asp:Label runat ="server" Text ="my test page " />
</asp:Content>


When i run the program it will run fine but when i click the button i mm getting following error on "Onclick= "getdata()"
error is => Microsoft JScript runtime error: Object expected
but when i remove
<script type = "text/ecmascript" src ="/hr/_layouts/Jquery/jquery-1.7.1.min.js"  />
<script type ="text/ecmascript"  src ="/hr/_layouts/SP.js"  />

and replace with
<SharePoint:ScriptLink name ="sp.js" LoadAfterUI= "true" Localizable ="false" runat ="server" />

I can click the  nutton without any error , BUT WHEN I USE THIS SHAREPOINT:SCRIPTLINK I CANT GET FOLLOWINGS
       txtCtx = SP.ClientContext.get_current();<= IT WONT GIVE THIS SP.SP.ClientContext.get_current()
        myweb = txtCtx.get_web();<=
        mylist = myweb.get_lists();<=


CAN SOME ONE HELP ME TO SOLVE THIS ISSUE

---

d.n weerasinghe

Answer 1

i think you need to post this in the SharePoint 2010 forums

kind regards,

paul Keijzers

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Answer 2

Hi d.n weerasinghe,

Thanks for your post!

Below is a sample code to access a list and display its title, please refer, and the main issue of your code is that you did not run your code asynchronous, so actually you need this line code like below:

ctx.executeQueryAsync(Function.createDelegate(this, this.onQuerySucceeded), Function.createDelegate(this, this.onQueryFailed));

The sample code:

<script type="text/ecmascript">
var list;
function runCode() {
   var ctx = new SP.ClientContext.get_current();
    var web = ctx.get_web();
    list = web.get_lists().getByTitle("list");
   ctx.load(list);
   ctx.executeQueryAsync(Function.createDelegate(this, this.onQuerySucceeded), Function.createDelegate(this, this.onQueryFailed));
}

function onQuerySucceeded() {
  alert(list.get_title());    
}

function onQueryFailed(sender, args) {
  alert('Request failed. ' + args.get_message() + '\n' + args.get_stackTrace());
}</script><input name="ClientDemo" onclick="runCode();" type="button" value="Get Current User"/> 

And you do not need this line:

<script type ="text/ecmascript"  src ="/hr/_layouts/SP.js"  /> OR <SharePoint:ScriptLink name ="sp.js" LoadAfterUI= "true" Localizable ="false" runat ="server" />

By default, SharePoint will load the SP.js automatically.

Thanks,
Simon

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Simon Huang

TechNet Community Support