Question

I don’t know if this question has been asked before. The way I know to do it am not convenient with it sometimes.

string[] exts = { "png", "jpg", "gif" };
if (exts.Contains(Path.GetExtension(filename)))
{
}

I would like to change the positions of the variables

if(Path.GetExtension(filename) is in exts)
{

}

Anyway to do it would be appreciated, LINQ, array function, etc

Answer 1

You can write an extension method on string that takes a string[] and tests whether the string is in the array (using Contains) – then you would have "aString".IsIn(myArray).

public static bool IsIn(this string toTest, string[] exts)
{
  return exts.Contains(toTest);
}


if(Path.GetExtension(filename).IsIn(exts))
{

}