In asp.net,how to use both code behind code and java script to the same control?

Mallika

14y

I can use both code behind and java script for the button control

e.g
Login.aspx file with 2 text box and submit button Using java script to validate user name/pass word text box as like below:
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Login.aspx.cs" Inherits="Login" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<script language = "javascript" >
    function validate() {
        if (document.getElementById("<%=txtUsername.ClientID%>").value == "") {
            alert("User name cannot be blank");
            document.getElementById("<%=txtUsername.ClientID%>").focus();
            return false;
        }
        if (document.getElementById("<%=txtPassword.ClientID%>").value == "") {
            alert("Password cannot be blank");
            document.getElementById("<%=txtPassword.ClientID%>").focus();
            return false;}

                   return true;}

</script>
    <title></title>
</head>
<body>
    <form runat="server" id = "LoginAuth" method ="post" >
    <div>
    UserName:
        <asp:TextBox ID="txtUsername" runat="server"></asp:TextBox>
        <br />

        Password:
        <asp:TextBox ID="txtPassword" runat="server"></asp:TextBox>
    <br />
        <asp:Button ID="cmdButton" runat="server" Text="Submit"
            onclick="cmdButton_Click" />

    </div>
    <asp:Label ID="lblMsg" runat="server" ></asp:Label>
    </form>
</body>
</html>

Login.aspx.cs
code behind file can have following code: to connect to db and add javascript function to the button control.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

using System.Data;
using System.Data.SqlClient;
using System.Configuration;//Configuration Manager
using System.Web.Security; //for FormAuthentication

public partial class Login : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        cmdButton.Attributes.Add("onclick", "return validate()");

    }
    protected void cmdButton_Click(object sender, EventArgs e)
    {
        if (Page.IsValid)
        {
            if (dbconn(txtUsername.Text.Trim(), txtPassword.Text.Trim())== true )
            {
                FormsAuthentication.RedirectFromLoginPage(txtUsername.Text, false );
            }
            else
            {
                lblMsg.Text = "Invalid UserName and Password€";

            }
        }
    }
    public bool dbconn(string u, string p)
    {

        SqlConnection conn = new SqlConnection();
        conn.ConnectionString = ConfigurationManager.ConnectionStrings["NWConn"].ConnectionString;
        conn.Open();
        SqlCommand cmd = new SqlCommand("sp_ValidateUser", conn);
        cmd.CommandType = CommandType.StoredProcedure;
        SqlParameter userParam, passwordparam, retValueparam;

        userParam = cmd.Parameters.Add("@UserName", SqlDbType.VarChar, 50) ;
        passwordparam=cmd.Parameters.Add("QPassWord", SqlDbType.VarChar, 50);
        retValueparam= cmd.Parameters.Add("@RetValue", SqlDbType.Int);

        userParam.Direction = ParameterDirection.Input;
        passwordparam.Direction = ParameterDirection.Input;
        retValueparam.Direction = ParameterDirection.ReturnValue ;

        userParam.Value = txtUsername.Text.ToString();
        passwordparam.Value = txtPassword.Text.ToString();
        //try
        //{

            if (conn.State == ConnectionState.Closed)
            {
                conn.Open();
                cmd.ExecuteNonQuery();

            }
            //Obtain the return value of the stored procedure into a variable
            int retValue = (int)retValueparam.Value;
            if (retValue < 1)
            {
                return false ;

            }
            else
            {

                //Return true to indicate that the login is successful
                return true;
            }


        //}

        //catch (Exception ex)
        //{

        //    lblMsg.Text = ex.Message + "Error connecting to DB";

        //}

        //return false;

    }

}

Mallika

14y

Please use the following method for using both the code behing and java script in the same control:

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

function btnClick() {

alert("Hello Hetalkumar!! How are you");

}

</script>

protected void Button1_Click(object sender, EventArgs e)

{

Response.Write("I am fine");

}

</script>

</head>

<body>

<div>

<asp:Button ID="Button1" runat="server" onclick="Button1_Click" Text="Button" OnClientClick="btnClick();" />

</div>

</form>

</body>

</html>

You have to define two separate code blocks for writing server side and client side code. And also need to associate the sever events to the server side methods/events and client events to the client side method/functions.

Hetalkumar Kachhadiya

14y

Hi Mallika

You can use code behind nad JavaScript on a same page like as follows:

Example:

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default2.aspx.cs" Inherits="Default2" ValidateRequest="false" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<script runat="server">
void btnSubmit_Click(Object sender, EventArgs e)
{
      Response.Write(txtString.Text);
}
</script>
</head>
   <body>
      <form id="form1" runat="server">
          <asp:TextBox ID="txtString" runat="server" Text="<script>alert('Hello ! Puru');</script>" />
          <asp:Button ID="btnSubmit" runat="server" OnClick="btnSubmit_Click" Text="Submit" />
      </form>
   </body>
</html>