Populate ASP.Net TextBox based on jQuery AutoComplete selection using C# and VB.Net

Hi mahjoubi,

Please refer below sample.

Database

I have made use of the following table Customers with the schema as follows. 

I have already inserted few records in the table.

You can download the database table SQL by clicking the download link below.

Download SQL file

HTML

<script src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.10.0.min.js" type="text/javascript"></script>
<script src="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.9.2/jquery-ui.min.js" type="text/javascript"></script>
<link href="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.9.2/themes/blitzer/jquery-ui.css"
    rel="Stylesheet" type="text/css" />
<script type="text/javascript">
    $(function () {
        $("[id*=txtName]").autocomplete({
            source: function (request, response) {
                $.ajax({
                    type: "POST",
                    url: '<%=ResolveUrl("~/Default.aspx/GetNames") %>',
                    data: "{ 'prefix': '" + request.term + "'}",
                    contentType: "application/json; charset=utf-8",
                    dataType: "json",
                    success: function (data) {
                        response($.map(data.d, function (item) {
                            return {
                                label: item.split('-')[0],
                                val: item.split('-')[1]
                            }
                        }))
                    },
                    error: function (response) {
                        alert(response.responseText);
                    }
                });
            },
            select: function (e, i) {
                $("[id$=hfName]").val(i.item.label);
                $.ajax({
                    type: "POST",
                    url: '<%=ResolveUrl("~/Default.aspx/GetCountry") %>',
                    data: "{ 'name': '" + i.item.label + "'}",
                    contentType: "application/json; charset=utf-8",
                    dataType: "json",
                    success: function (response) {
                        $("[id*=txtCountry]").val(response.d);
                    },
                    error: function (response) {
                        alert(response.responseText);
                    }
                });
            },
            minLength: 0
        });
    });
</script>
<table>
    <tr>
        <td>Enter Name:
        </td>
        <td>
            <asp:TextBox ID="txtName" runat="server" />
        </td>
        <td>
            <asp:HiddenField ID="hfName" runat="server" />
        </td>
    </tr>
    <tr>
        <td>Country:
        </td>
        <td>
            <asp:TextBox ID="txtCountry" runat="server" />
        </td>
        <td></td>
    </tr>
</table>

Namespaces

C#

using System.Web.Services;
using System.Configuration;
using System.Data.SqlClient;
using System.Collections.Generic;

VB.Net

Imports System.Web.Services
Imports System.Configuration
Imports System.Data.SqlClient
Imports System.Collections.Generic

Code

C#

[WebMethod]
public static string[] GetNames(string prefix)
{
    List<string> customers = new List<string>();
    using (SqlConnection conn = new SqlConnection())
    {
        conn.ConnectionString = ConfigurationManager.ConnectionStrings["conString"].ConnectionString;
        using (SqlCommand cmd = new SqlCommand())
        {
            cmd.CommandText = "SELECT CustomerId, Name FROM Customers WHERE Name LIKE @SearchText + '%'";
            cmd.Parameters.AddWithValue("@SearchText", prefix);
            cmd.Connection = conn;
            conn.Open();
            using (SqlDataReader sdr = cmd.ExecuteReader())
            {
                while (sdr.Read())
                {
                    customers.Add(string.Format("{0}-{1}", sdr["Name"], sdr["CustomerId"]));
                }
            }
            conn.Close();
        }
    }
    return customers.ToArray();
}

[WebMethod]
public static string GetCountry(string name)
{
    string country = string.Empty;
    using (SqlConnection conn = new SqlConnection())
    {
        conn.ConnectionString = ConfigurationManager.ConnectionStrings["conString"].ConnectionString;
        using (SqlCommand cmd = new SqlCommand())
        {
            cmd.CommandText = "SELECT TOP 1 Country FROM Customers WHERE Name = @Name";
            cmd.Parameters.AddWithValue("@Name", name);
            cmd.Connection = conn;
            conn.Open();
            country = Convert.ToString(cmd.ExecuteScalar());
            conn.Close();
        }
    }
    return country;
}

VB.Net

<WebMethod>
Public Shared Function GetNames(ByVal prefix As String) As String()
    Dim customers As List(Of String) = New List(Of String)()
    Using conn As SqlConnection = New SqlConnection()
        conn.ConnectionString = ConfigurationManager.ConnectionStrings("conString").ConnectionString
        Using cmd As SqlCommand = New SqlCommand()
            cmd.CommandText = "SELECT CustomerId, Name FROM Customers WHERE Name LIKE @SearchText + '%'"
            cmd.Parameters.AddWithValue("@SearchText", prefix)
            cmd.Connection = conn
            conn.Open()
            Using sdr As SqlDataReader = cmd.ExecuteReader()
                While sdr.Read()
                    customers.Add(String.Format("{0}-{1}", sdr("Name"), sdr("CustomerId")))
                End While
            End Using
            conn.Close()
        End Using
    End Using
    Return customers.ToArray()
End Function

<WebMethod>
Public Shared Function GetCountry(ByVal name As String) As String
    Dim country As String = String.Empty
    Using conn As SqlConnection = New SqlConnection()
        conn.ConnectionString = ConfigurationManager.ConnectionStrings("conString").ConnectionString
        Using cmd As SqlCommand = New SqlCommand()
            cmd.CommandText = "SELECT TOP 1 Country FROM Customers WHERE Name = @Name"
            cmd.Parameters.AddWithValue("@Name", name)
            cmd.Connection = conn
            conn.Open()
            country = Convert.ToString(cmd.ExecuteScalar())
            conn.Close()
        End Using
    End Using
    Return country
End Function

Screenshot