http://www.codeproject.com/KB/sharepoint/SP2010ClientObjectModel.aspx

and one more MSDN link

http://msdn.microsoft.com/en-us/library/ee534956.aspx

Required files

• SPAPI_Core.js
• SPAPI_Lists.js

Procedure:

• You can download these files from Internet (You can download from the link)
• First create one List sharepoint site with the name ‘Employee’ and fields should be ‘Title‘ & ‘Department’. Deprtment field should be LookUp field. Take data from another list with the department names.
  
• Upload above mentioned two files into ‘Shared document library‘
• Open that site in SharePoint designer
• Create a ‘InsertItem.aspx‘ in  ‘Shared documents’ library.
• Write below code in the page.

<asp:Content id=”Content1″ runat=”Server” contentplaceholderid=”PlaceHolderMain”>

<script language=”javascript” type=”text/javascript” src=”http://192.168.1.137:5555/Shared%20Documents/SPAPI_Core.js“></script>
<script language=”javascript” type=”text/javascript” src=”http://192.168.1.137:5555/Shared%20Documents/SPAPI_Lists.js“></script>
<script language=”javascript” type=”text/javascript” src=”http://192.168.1.137:5555/Shared%20Documents/InsertItem.js“></script>

<table style=”font-family:Calibri;width:25%”>
<tr>
<td>
Title:
</td>
<td> <input type=”text” id=”txtTitle”></td>
</tr>
<tr><td>Department:</td>
<td><select id=”txtDepartment”>
<option value=”0″>Dept</option>
<option value=”1″>Dept1</option>
<option value=”2″>Dept2</option>
<option value=”3″>Dept3</option>
</select>

</td>
</tr>

<tr><td></td><td><button type=”submit” onclick=”AddEmployee();”>Insert</button></td></tr>
</table>
</asp:Content>

<asp:Content id=”Content2″ runat=”Server” contentplaceholderid=”PlaceHolderPageTitle”>
Insert Form
</asp:Content>

• After above created page, please create a JavaScript file ‘InsertCode.js‘ file with the below code.

var strUrl=”http://win2003:5555/“;
var splists = new SPAPI_Lists(strUrl);
var spuser = new SPAPI_UserGroup(strUrl);

function AddEmployee()
{
if(document.getElementById(“txtTitle”).value==”"||document.getElementById(“txtDepartment”).value==”")
{
if(document.getElementById(“txtTitle”).value==”")
{
alert(‘Employee name Required..’);
}
if(document.getElementById(“txtDepartment”).value==”")
{
alert(‘Department name Required..’);
}
}
else
{
InsertItem();
}
}

function InsertItem()
{
var lists=new SPAPI_Lists(strUrl);
var empName=document.getElementById(“txtTitle”).value;
var department=document.getElementById(“txtDepartment”).value;
alert(“Employee Name:”+empName);
var batch=”<Batch PreCalc=’TRUE’ OnError=’Continue’><Method ID=’1′ Cmd=’New’><Field Name=’Title’>”+document.getElementById(“txtTitle”).value+”</Field><Field Name=’Department’ Type=’LookUp’ LookUpID=’True’>”+document.getElementById(‘txtDepartment’).value+”</Field></Method></Batch>”;
var res = lists.updateListItems(“Employee”,batch);
if(res.status==200)
{
alert(‘Record Saved Successfully’);
}
else
{
alert(res.responseText);
}
}

• The above file will help to insert the item using the SPAPI files which are recommended to download from internet.
• Now open the ‘InsertTem.aspx‘ page and test the functionality.

First Video

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Please post your comments and extra links if you have knew..

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After visited this post please post your comments and any other stuff…

Please watch this below video.

http://www.microsoft.com/resources/msdn/en-us/office/media/MOSS2007CreateSeqWFUsingVS2008.wvx

http://nickgrattan.wordpress.com/2007/09/06/showing-recent-items-in-a-sharepoint-view/

Reset IIS

http://ktskumar.wordpress.com/2009/03/09/the-security-validation-for-this-page-is-invalid-click-back-in-your-web-browser-refresh-the-page-and-try-your-operation-again/

I got this above error even after I written the code in

SPSecurity.RunWithElevatedPrivileges(delegate()

{

—– CODE—-

});

Then I got solution from this below page

http://www.directsharepoint.com/2011/03/access-denied-error-while-using.html

Solution :

Write code as below

SPWeb web = SPContext.Current.Web;

SPSecurity.RunWithElevatedPrivileges(delegate()
{
using (SPSite elevatedSite = new SPSite(web.Site.ID))
{
SPWeb elevatedWeb = elevatedSite.OpenWeb(web.ID);
SPUser someUser = elevatedWeb.EnsureUser(web.CurrentUser.LoginName);
}
});

It will resolve the issue.