Question

I have a function that, among other things, takes in an object and a Type, and converts the object into that Type. However, the input object is often a double, and the type some variation of int (uint, long, etc.). I want this to work if a round number is passed in as a double (like 4.0), but to throw an exception if a decimal is passed in (4.3). Is there any more elegant way to check if the Type is some sort of int?

if (inObject is double && (targetType == typeof (int)                          || targetType == typeof (uint)                          || targetType == typeof (long)                          || targetType == typeof (ulong)                          || targetType == typeof (short)                          || targetType == typeof (ushort))) {     double input = (double) inObject;     if (Math.Truncate(input) != input)         throw new ArgumentException('Input was not an integer.'); } 

Thanks.

Answer 1

This seems to do what you ask. I have only tested it for doubles, floats and ints.

    public int GetInt(IConvertible x)     {         int y = Convert.ToInt32(x);         if (Convert.ToDouble(x) != Convert.ToDouble(y))             throw new ArgumentException('Input was not an integer');         return y;     }