enum contains any of these values?

[Guest]

Hi,

Consider I have an enum like so:

enum Age {
Baby = 1,
Child = 2,
Teen = 4,
Adult = 8,
Senior = 16
}

Age age = GetAge();
if ((age == Age.Baby) || (age == Age.Child) || .... ) {
// Do something.
}

Is it possible to make the statement above more compact? ie. could I maybe
use enum flags to reduce it.

This obviously will not work:

enum Age {
Baby = 1,
Child = 2,
Teen = 4,
Adult = 8,
Senior = 16,
BelowEighteen = Baby | Child | Teen
}

if (age == Age.BelowEighteen) {
//Do something
}

I am using .net 2.0
Thanks in advance.

 

[Truong Hong Thi]

This obviously will not work:

enum Age {
Baby = 1,
Child = 2,
Teen = 4,
Adult = 8,
Senior = 16,
BelowEighteen = Baby | Child | Teen }
if (age == Age.BelowEighteen) {
//Do something
}

Hi STech, in that case you could try:
if ((age & Age.BelowEighteen) != 0) {
//Do something
}

Personally, I think it is more readable to define a function like:
bool IsBelow18(age) {
return (age == Age.Baby) || (age == Age.Child) || ....;
}

 

[Guest]

Hi STech,

Great question, I took a look at it. This is the code I came up with.

[Flags]
private enum Age
{
Baby = 1,
Child = 2,
Teen = 4,
Adult = 8,
Senior = 16,
BelowEighteen = Baby | Child | Teen
}

private void button1_Click(object sender, System.EventArgs e)
{
Age age = Age.Child;
int found = Age.BelowEighteen.ToString().IndexOf(age.ToString());
if(found > -1)
{
MessageBox.Show( "Below Eighteen");
}


I't probably not the best performant solution but I didn't find any other way.
Hope it's of use to you.

 

[jmcgrew]

You were close. You can use bitwise operators to check more than one
value at once:

if ((age & Age.BelowEighteen) != 0) {
// age is Baby, Child, or Teen
}

Jesse