[c#] How to make an autocomplete TextBox in ASP.NET?

How do I make an autocomplete TextBox in C# that binds to a data source?

aspx Page Coding

<form id="form1" runat="server">
       <input type="search" name="Search" placeholder="Search for a Product..." list="datalist1"
                    required="">
       <datalist id="datalist1" runat="server">

       </datalist>
 </form>

.cs Page Coding

protected void Page_Load(object sender, EventArgs e)
{
     autocomplete();
}
protected void autocomplete()
{
    Database p = new Database();
    DataSet ds = new DataSet();
    ds = p.sqlcall("select [name] from [stu_reg]");
    int row = ds.Tables[0].Rows.Count;
    string abc="";
    for (int i = 0; i < row;i++ )
        abc = abc + "<option>"+ds.Tables[0].Rows[i][0].ToString()+"</option>";
    datalist1.InnerHtml = abc;
}

Here Database is a File (Database.cs) In Which i have created on method named sqlcall for retriving data from database.

1-Install AjaxControl Toolkit easily by Nugget

PM> Install-Package AjaxControlToolkit

2-then in markup

<asp:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server">  
</asp:ToolkitScriptManager>  

<asp:TextBox ID="txtMovie" runat="server"></asp:TextBox>  

<asp:AutoCompleteExtender  ID="AutoCompleteExtender1"  TargetControlID="txtMovie"   
    runat="server" />  

3- in code-behind : to get the suggestions

[System.Web.Services.WebMethodAttribute(),System.Web.Script.Services.ScriptMethodAttribute()]  
    public static string[] GetCompletionList(string prefixText, int count, string contextKey) {  
        // Create array of movies  
        string[] movies = {"Star Wars", "Star Trek", "Superman", "Memento", "Shrek", "Shrek II"};  

        // Return matching movies  
        return (from m in movies where m.StartsWith(prefixText,StringComparison.CurrentCultureIgnoreCase) select m).Take(count).ToArray();  
    }

source: http://www.asp.net/ajaxlibrary/act_autocomplete_simple.ashx

Try this: .aspx page

<td>  
<asp:TextBox ID="TextBox1" runat="server" AutoPostBack="True"OnTextChanged="TextBox1_TextChanged"></asp:TextBox>  
<asp:AutoCompleteExtender ServiceMethod="GetCompletionList" MinimumPrefixLength="1"  
   CompletionInterval="10" EnableCaching="false" CompletionSetCount="1" TargetControlID="TextBox1"  
   ID="AutoCompleteExtender1" runat="server" FirstRowSelected="false">  
      </asp:AutoCompleteExtender>  

Now To auto populate from database :

public static List<string> GetCompletionList(string prefixText, int count)  
    {  
        return AutoFillProducts(prefixText);  

    }  

    private static List<string> AutoFillProducts(string prefixText)  
    {  
        using (SqlConnection con = new SqlConnection())  
        {  
            con.ConnectionString = ConfigurationManager.ConnectionStrings["Conn"].ConnectionString;  
            using (SqlCommand com = new SqlCommand())  
            {  
                com.CommandText = "select ProductName from ProdcutMaster where " + "ProductName like @Search + '%'";  
                com.Parameters.AddWithValue("@Search", prefixText);  
                com.Connection = con;  
                con.Open();  
                List<string> countryNames = new List<string>();  
                using (SqlDataReader sdr = com.ExecuteReader())  
                {  
                    while (sdr.Read())  
                    {  
                        countryNames.Add(sdr["ProductName"].ToString());  
                    }  
                }  
                con.Close();  
                return countryNames;  
            }  
        }  
    }  

Now:create a stored Procedure that fetches the Product details depending on the selected product from the Auto Complete Text Box.

Create Procedure GetProductDet  
(  
@ProductName varchar(50)    
)  
as  
begin  
Select BrandName,warranty,Price from ProdcutMaster where ProductName=@ProductName  
End   

Create a function name to get product details ::

private void GetProductMasterDet(string ProductName)  
    {  
        connection();  
        com = new SqlCommand("GetProductDet", con);  
        com.CommandType = CommandType.StoredProcedure;  
        com.Parameters.AddWithValue("@ProductName", ProductName);  
        SqlDataAdapter da = new SqlDataAdapter(com);  
        DataSet ds=new DataSet();  
        da.Fill(ds);  
        DataTable dt = ds.Tables[0];  
        con.Close();  
        //Binding TextBox From dataTable  
        txtbrandName.Text =dt.Rows[0]["BrandName"].ToString();  
        txtwarranty.Text = dt.Rows[0]["warranty"].ToString();  
        txtPrice.Text = dt.Rows[0]["Price"].ToString();   
    }

Auto post back should be true

<asp:TextBox ID="TextBox1" runat="server" AutoPostBack="True" OnTextChanged="TextBox1_TextChanged"></asp:TextBox>

Now, Just call this function

protected void TextBox1_TextChanged(object sender, EventArgs e)  
  {  
      //calling method and Passing Values  
      GetProductMasterDet(TextBox1.Text);  
  } 

I use ajaxcontrol toolkit's AutoComplete