Check username and password is incorrect in asp.net

Guest User

when user login if username is incorrect then it will show error if password is incorrect its shows error...in my code its is username or password is incorrect then it will show error.. i want for both condition.this all done by Entity Framework

protected void Button1_Click(object sender, EventArgs e)

{

string UserName = TxtUserName.Text;

WallpaperEntities4 db = new WallpaperEntities4();

string ID = Request.QueryString["Id"];

string query = (from c in db.Users

where c.UserName == TxtUserName.Text && c.Password == TxtPassword.Text

select c.UserName).FirstOrDefault();

if (query != null)

{

Session["UserName"] = UserName;

Response.Redirect("/Walpaper.aspx?username="+UserName);

}

else

LblMesge.Text = "Invalid User or password";

}

6 Replies

Know the answer? Post it — somebody with the same question will find it here.

Varun Setia6y ago
Accepted answer
1. bool user = (from c in db.Users
2. where c.UserName == TxtUserName.Text
3. select c).FirstOrDefault();
5. if(user == null){
6. LblMesge.Text = "Invalid Username";
7. }else if(!user.Password.Equals(TxtPassword.Text)){
8. LblMesge.Text = "Invalid Password";
9. }else{
10. string UserName = TxtUserName.Text;
  WallpaperEntities4 db = new WallpaperEntities4();
  string ID = Request.QueryString["Id"];
  Session["UserName"] = UserName;
  Response.Redirect("/Walpaper.aspx?username="+UserName);
11. }
This is how it will look like, Please test it properly :)

Guest User6y ago

This is working code.

Thanx once again Varun Setia...

protected void Button1_Click(object sender, EventArgs e)

{

using (var context = new WallpaperEntities4())

{

string UserName = Convert.ToString(Session["UserName"]);

User user = (from c in context.Users

where c.UserName == TxtUserName.Text

select c).FirstOrDefault();

if (user == null)

{

LblMesge.Text = "Invalid Username";

}

else if (!user.Password.Equals(TxtPassword.Text))

{

LblMesge.Text = "Invalid Password";

}

else

{

WallpaperEntities4 db = new WallpaperEntities4();

string ID = Request.QueryString["Id"];

Session["UserName"] = UserName;

Response.Redirect("/Walpaper.aspx?username=" + UserName);

}

Guest User6y ago

Varun

cant i put in if else condition....

Varun Setia6y ago

bool usernameExists = (from c in db.Users
where c.UserName == TxtUserName.Text
select c).Count() >0;
if(usernameExists){
string UserName = TxtUserName.Text;
WallpaperEntities4 db = new WallpaperEntities4();
string ID = Request.QueryString["Id"];
string query = (from c in db.Users
where c.UserName == TxtUserName.Text && c.Password == TxtPassword.Text
select c.UserName).FirstOrDefault();
if (query != null)
{
Session["UserName"] = UserName;
Response.Redirect("/Walpaper.aspx?username="+UserName);
}
else
LblMesge.Text = "Invalid password";
}
}else{
//No username exists logic
LblMesge.Text = "Invalid User";
}

Try this :)

Guest User6y ago

i am ot facing any error... i want to show if username is incorrect then show username is incorrect and if password is incorrect then show password is incorrect

Jenith Thakkar6y ago

What kind of error you're facing with above code?