The example illustrates simple login form using Asp.Net

Introduction

In this example I will create simple login form using SQL in Asp.Net. Let's see step by step.

Login page

Let's create a simple login page.

            <table>
                <tr>
                    <td>User Name:</td>
                    <td><asp:TextBox ID="txtUserName" runat="server"></asp:TextBox></td>
                </tr>
                <tr>
                    <td>Password:</td>
                    <td><asp:TextBox ID="txtPassword" runat="server" TextMode="Password"></asp:TextBox></td>
                </tr>
                <tr>
                    <td>
                        <asp:Button ID="btnSubmit" runat="server" Text="Login" OnClick="btnSubmit_Click" />
                    </td>
                    <td>
                        <asp:Label ID="mess" runat="server"></asp:Label>
                    </td>
                </tr>
            </table>

Code behind

Patte below code to perform login.

    protected void btnSubmit_Click(object sender, EventArgs e)
    {
        if(!string.IsNullOrWhiteSpace(txtUserName.Text) && !string.IsNullOrWhiteSpace(txtPassword.Text))
        {
            cstring.Open();
            SqlCommand cmd1 = new SqlCommand("select * from userLogin where username='" + txtUserName.Text.Trim() + "' and Password='" + txtPassword.Text + "'", cstring);
            SqlDataReader dr = cmd1.ExecuteReader();
            if (dr.HasRows)
            {
                dr.Read();
                string  usr = dr[2].ToString();
                FormsAuthentication.RedirectFromLoginPage(usr, false);
                Session["user"] = dr["UserName"].ToString();
                dr.Close();
               
            }
            else
            {
                mess.Text = "Please enter correct user name, password..";
            }
            cstring.Close();

        }

        else
        {
            mess.Text = "Please enter correct user name, password..";
        }
    }

Hop this can help you.