c# - Specified cast is not valid.. how to resolve this

Question

I have the below function

public object Convert(object value)
 {
    string retVal = string.Empty;
    int oneMillion = 1000000;
    retVal = ((double)value / oneMillion).ToString("###,###,###.###");
    return retVal;
 }

I am invoking like

var result  = Convert(107284403940);

Error: "Specified cast is not valid."

how to fix...

Note:~ the object value can be double, decimal, float, integer(32 and 64)..anything

Is it possible to do the typecasting at runtime?

Answer 1

Use Convert.ToDouble(value) rather than (double)value. It takes an object and supports all of the types you asked for! :)

Also, your method is always returning a string in the code above; I'd recommend having the method indicate so, and give it a more obvious name (public string FormatLargeNumber(object value))