AJAX

[ritu verma]

I know how to fetch the records from DB,But i want to ask u just small thing.

SQL TABLE

roll                name                  marks
1                    Ritu                       10
2                    Sneha                    20
3                    Ruchi                       30

CODE BEHIND PAGE
Default.aspx

protected void Page_Load(object sender, EventArgs e)
    {
        cmbRoll.Items.Add("--Select--");
        cmbRoll.Items.Add("1");
        cmbRoll.Items.Add("2");
        cmbRoll.Items.Add("3"); 
 
        cmbRoll.Attributes.Add("onChange", "javascript:return check()");  
 
    }

JS CODE

<title>Untitled Page</title>
    <script type ="text/javascript" language ="javascript">
    var xmlHttp;
    var WholeString;
    var col_array;
    
    function check()
    {
    var Roll=document.getElementById("<%=cmbRoll.ClientID %>").value;
     //checkXHR("Retrieve.aspx?Roll=" + Roll + "&sid="+Math.random());
    checkXHR("Retrieve.aspx?Roll=" + Roll );
                  
    WholeString=document.getElementById("hd1").value;
     alert (WholeString); //Result of Particular roll No that is fetched from DB thru AJAX
     col_array=WholeString.split("^^^^");
    for (i = 0; i <= col_array.length; i++)
    {
     
    document.getElementById("txtName").value=col_array[1];
     document.getElementById("txtMarks").value=col_array[2];
      
    }
      
        xmlHttp=null;
                return true;
    }
    
    function checkXHR(url)
    {
       try
       {
         xmlHttp=new XMLHttpRequest();        
       }
       catch (e)
       {
         try
         {
            xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
         }
         catch (e)
         {
            try
            {
                xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");                
            }
            catch (e)
            {
                alert("Your browser does not support AJAX!");
                return false;
            }
         }
       }
      
       xmlHttp.open("GET",url,false);       
       xmlHttp.onreadystatechange=statechanged;
       xmlHttp.send(null);
    }
    
    function statechanged()
    {
       if(xmlHttp.readyState==4)
       {
         document.getElementById("hd1").value = xmlHttp.responseText;
       }
       else
       {
         document.getElementById("hd1").value="";
       }         
    }

Retrieve.aspx

protected void Page_Load(object sender, EventArgs e)
    {
        string a;
        string b;
        string c;

        SqlDataAdapter da = new SqlDataAdapter("select * from [Information] where upper(roll)='" +
                           Request["Roll"].ToUpper() + "'", conn);
        DataSet ds = new DataSet();
        da.Fill(ds);
              
        foreach(DataRow row in ds.Tables[0].Rows) 
        {
            a = row[0].ToString();
            b = row[1].ToString();
            c = row[2].ToString();
  
            Response.Write(a + "^^^^" + b + "^^^^" + c);
         
        }

I take hidden field in Default.aspx & as u know response.write to hidden field..SO in Default.aspx I m getting my result back in variable in the line

WholeString=document.getElementById("hd1").value;

Now I have employee info in database & i want to bind it to the Gridview using AJAX...Even for that i have to return value in the above way or there is other way out..

Plz help me out!!!