I am a VB programmer tring to learn C#

I am stuck on a bit operator "&"

in VB:
' checkLogin = 3 means "Login exists" and "Employee Number exists"
If (checkLogin And 1) Then
lbError.Text = "Login already exists"
End If
If (checkLogin And 2) And txtEmpNum.Text <> 0 Then
lbError.Text &= "Employee Number already exists"
End If

I did this in C#:
if(checkLogin & 1)
{
lbError.Text = "Login already exists";
}
if((checkLogin & 2) & txtEmpNum.Text.Length > 0 )
{
lbError.Text = "Employee Number already exists";
}

Error:
Cannot implicitly convert type 'int' to 'bool'



--
Thanks in advance,
Dave

in C# if you type & it is bit AND operator, it returs int, that is the
reason why the compiler generated error.

In order to get boolean AND comparison you have to write &&

if(checkLogin && 1)
{ }

--
Vadym Stetsyak aka Vadmyst
http://vadmyst.blogspot.com

"Dave" <Dave (AT) discussions (DOT) microsoft.com> wrote

use && instead of &

"Dave" wrote:

logical expression must be composed of boolean operands. int is not boolean.
you'll have to write it like this

int a;
(checkLogin && (a == 1))
{
...
}

by asking if a's value is some value you have made boolean expression out of
int . numerical value doesn't evaluate to true/false (c# being strongly
typed, unlike c++). also && is logical operator and & bitwise

"Dave" wrote:

Unless I'm mistaken, '&' is also a logical boolean operator if both
operands are boolean.

The correct answer to the problem, since he is using a bitmask to
check/set multiple options, is:

if ((checkLogin & 1) != 0)
lbError.Text = "Login already exists";

if (((checkLogin & 2) != 0) & (txtEmpNum.Text.Length > 0))
lbError.Text = "Employee Number already exists";

Could also use:

if (((checkLogin & 2) != 0) && (txtEmpNum.Text.Length > 0))
lbError.Text = "Employee Number already exists";

for the second statement. Since && is a conditional logical boolean
operator, C# will not evaluate the second test if the first is false
since the overall boolean value can not be true if the first is false.

"ondrejbohaciak" <ondrejbohaciak (AT) discussions (DOT) microsoft.com> wrote: