Filter GridView on TextBox Keypress using jQuery in ASP.Net

I have this code that am tryimg to create a search box by Like % as am typing the letters its showing the users. But this code is just displaying all users on page then after typing i have to click button before the users shows. Please how do i get this done?

HTML

<form id="form1" runat="server">
<div>
    <table>
        <tr>
            <td>
                Search
            </td>
            <td>
                <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
            </td>
            <td>
                <asp:Button ID="Button1" runat="server" Text="Go" OnClick="Button1_Click" />
            </td>
        </tr>
    </table>
    <table>
        <tr>
            <td>
                <p>
                    <asp:Label ID="Label2" runat="server" Text="label"></asp:Label>
                </p>
            </td>
        </tr>
    </table>
    <asp:GridView ID="GridView1" runat="server">
    </asp:GridView>
</div>
</form>

C#

using System;
using System.Data;
using System.Configuration;
using System.Data.SqlClient;

public partial class _Default : System.Web.UI.Page
{
    public SqlConnection con;
    public string constr;

    public void connection()
    { 
        constr=ConfigurationManager.ConnectionStrings["emp"].ToString();
        con = new SqlConnection(constr);
        con.Open();    
    }

    protected void Page_Load(object sender, EventArgs e)
    {
        Label1.Visible = false;
    }

    private void rep_bind()
    {
        connection();
        string query = "select * from emp where Name like'" + TextBox1.Text + "%'";

        SqlDataAdapter da = new SqlDataAdapter(query, con);
        DataSet ds = new DataSet();
        da.Fill(ds);
        GridView1.DataSource = ds;
        GridView1.DataBind();
    }
  
    protected void Button1_Click(object sender, EventArgs e)
    {
        connection();
        string query = "select Name  from emp where Name like'" + TextBox1.Text + "%'";
        SqlCommand com = new SqlCommand(query, con);
        SqlDataReader dr;
        dr = com.ExecuteReader();
        if (dr.HasRows)
        {
            dr.Read();
            rep_bind();
            GridView1.Visible = true;
            TextBox1.Text = "";
            Label1.Text = "";
        }
        else
        {
            GridView1.Visible = false;        
            Label1.Visible = true;
            Label1.Text = "The search Term " + TextBox1.Text + "  Is Not Available in the Records";
        }
    }
}