checking if value is one of a group

[impeham]

Hi. let's say i have the following code: int x; ... // some code if ((x == 1) || (x == 5) || (x == 7) || (x == 9)) { ... /some code } is there an elegant way to code it without repeating the x object? i thought about something like: if (x == (1 || 5 || 7 || 9)) Thanks

[J4amieC]

not really, other than switch(x) { case 1: case 3: case 5: case 7: // do something break; } but this is more longwinded than the aforementioned if (x==1 || x==3 || x==5 || x==7) method

--- How to get answers to your questions[^]

[Robert Rohde]

Hi, another possibility:

if (Array.IndexOf(new int[] { 1, 5, 7, 9 }, x) >= 0) {
//...
}

If you store the array in some field it would be shorter (and more efficient when called often):

//somewhere in your class
private int[] _goodNumbers = new int[] { 1, 5, 7, 9 };

//your method
if (Array.IndexOf(_goodNumbers, x) >= 0) {
//...
}

Robert