C# How do I check if one of two values is TRUE?

Question

Hi all,

Should be a simple question for the C# experts here.

I basically want to check if one value or another is TRUE, a wild stab at the code is below:

if ((Boolean.Parse(staff.getValue("Male")) | Boolean.Parse(staff.getValue("Female")))    
{   
   // is true
}

Is this correct?

Thanks

Answer 1

bool isMale = Boolean.Parse(staff.getValue("Male");
bool isFemale = Boolean.Parse(staff.getValue("Female");
if (isMale || isFemale) // note double pipe ||
{
   // do something if true
}

Answer 2

Sounds like you're looking for the logical OR.

if(condition1 || condition2)
{
}

Answer 3

The conditional OR operator || is what you need

if ((Boolean.Parse(staff.getValue("Male")) || Boolean.Parse(staff.getValue("Female")))
{
   //is true
}

If the first condition is TRUE, then the second condition isn't checked since the outcome is obviously going to return TRUE.

Answer 4

A little exception checking is needed anyway. The Boolean.Parse() method gets a string as argument and returns either true or false only if the argument, once stripped out of whitespace, is equal to "True" or "False" (note capitalization). In ANY other case the function returns an exception.

Supposing that the possible values of staff.getValue("Male") and staff.getValue("Female") are exactly those two, then the simple disjunction (||) is sufficient. If any other return value is possible, including null and the empty string, then you have to check for exceptions

bool isMale;
try {
    isMale = Boolean.Parse(staff.getValue("Male"));
} catch(Exception e) {
    isMale = Boolean.False;
}
try {
    isFemale = Boolean.Parse(staff.getValue("Female"));
} catch(Exception e) {
    isFemale = Boolean.False;
}
if (isMale || isFemale) // note double pipe ||
{
    // do something if true
}

or compare manually

bool isMale = Boolean.TrueValue == staff.getValue("Male");
bool isFemale = Boolean.TrueValue == staff.getValue("Female");
if (isMale || isFemale) // note double pipe ||
{
    // do something if true
}

Answer 5

If EXACTLY ONE should be true then it is:

var male = bool.Parse(staff.getValue("Male"));
var female = bool.Parse(staff.getValue("Female"));

if (male ^ female)    
{
   //is true
}

Answer 6

To indicate whether a gender is specified with a value of "true" rather than "false",

bool genderIsSpecified = staff.getValue("Male") | staff.getValue("Female");

.. will only determine whether it's one of those values, not which of those values the object staff is.

So, just in case this question is literal and not an abstract example, ...

Male or Female .. everyone is one or the other. Perhaps in your question you meant to ask which of the two is the case? In that case,

bool defaultGenderIfNoGenderDocumented = true; // male
bool MaleIfTrue_FemaleIfFalse = !string.IsNullOrEmpty(staff.getValue("Male"))
    ? bool.Parse(staff.getValue("Male"))
    : string.IsNullOrEmpty(staff.getValue("Female"))
        ? bool.Parse(staff.getValue("Female"))
            ? false
            : defaultGenderIfNoGenderDocumented
        : defaultGenderIfNoGenderDocumented;

Or simply,

// assume value is properly populated, ignore "Female" value
bool isMale = bool.Parse(staff.getValue("Male")); 

Answer 7

Note that TryParse works more fast and more safe then just Parse because doesn't throw an exception in case of error. TryParse returns bool that indicates was parse successful or was not.

So both parsing methods should return true and only after that - do the main check

bool male, female;
if ((Boolean.TryParse(staff.getValue("Male"), out male) && 
     Boolean.TryParse(staff.getValue("Female"), out female)) &&
    (male || female)) // or ^
{
    // do stuff
}

or

bool male, female;
if (Boolean.TryParse(staff.getValue("Male"), out male) &&
     Boolean.TryParse(staff.getValue("Female"), out female))        
{
    if(male) { }
    else if (female) { } // or just else
}
else
{
     // staff contains wrong data. Probably "yeap" instead of "true"
}