Cascading TextBox in ASP.Net

Hi,

Here I have crearted sample that will help you out.

HTML

<div>
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
    <script type="text/javascript">
        $(function () {
            $('[id*=txtCode]').on('keyup', function () {
                $.ajax({
                    type: "POST",
                    url: "Default.aspx/GetName",
                    data: '{code: "' + $(this).val() + '" }',
                    contentType: "application/json; charset=utf-8",
                    dataType: "json",
                    success: function (response) {
                        var lst = response.d;
                        if (lst != null || lst != '') {
                            $('[id*=txtName]').val(lst.split('-')[0]);
                            $('[id*=txtPrice]').val(lst.split('-')[1]);
                        }
                    },
                    failure: function (response) {
                        alert(response.d);
                    }
                });
                return false;
            })
        });
    </script>
    Product Code:
    <asp:TextBox ID="txtCode" runat="server" />
    <br />
    <br />
    Product Name:
    <asp:TextBox ID="txtName" runat="server" />
    <br />
    <br />
    Product Price:
    <asp:TextBox ID="txtPrice" runat="server" />
</div>

c#

[System.Web.Services.WebMethod]
public static string GetName(string code)
{
    DataTable dt = new DataTable();
    dt.Columns.Add("code");
    dt.Columns.Add("name");
    dt.Columns.Add("Price");
    dt.Rows.Add("10", "Nokia 1200", 1200);
    dt.Rows.Add("11", "Mi4", 8000);
    dt.Rows.Add("12", "Sony Xperia Z1", 51000);
    dt.Rows.Add("13", "iphone 6 plus 128GB", 67000);
    DataRow data = (from row in dt.AsEnumerable()
                    where row["code"].ToString() == code
                    select row).FirstOrDefault();
    string result = string.Empty;
    if (data != null)
        result = string.Format("{0}-{1}", data["name"].ToString(), data["price"].ToString());
    return result;
}

vb

<System.Web.Services.WebMethod> _
Public Shared Function GetName(code As String) As String
    Dim dt As New DataTable()
    dt.Columns.Add("code")
    dt.Columns.Add("name")
    dt.Columns.Add("Price")
    dt.Rows.Add("10", "Nokia 1200", 1200)
    dt.Rows.Add("11", "Mi4", 8000)
    dt.Rows.Add("12", "Sony Xperia Z1", 51000)
    dt.Rows.Add("13", "iphone 6 plus 128GB", 67000)
    Dim data As DataRow = (From row In dt.AsEnumerable() Where row("code").ToString() = coderow).FirstOrDefault()
    Dim result As String = String.Empty
    If data IsNot Nothing Then
        result = String.Format("{0}-{1}", data("name").ToString(), data("price").ToString())
    End If
    Return result
End Function

Screenshot