Test if Convert.ChangeType will work between two types

I was just encountering this same issue, and I used Reflector to look at the source for ChangeType. ChangeType throws exceptions in 3 cases:

1. conversionType is null
2. value is null
3. value does not implement IConvertible

After those 3 are checked, it is guaranteed that it can be converted. So you can save a lot of performance and remove the try{}/catch{} block by simply checking those 3 things yourself:

public static bool CanChangeType(object value, Type conversionType)
{
    if (conversionType == null)
    {
        return false;
    }

    if (value == null)
    {              
        return false;
    }

    IConvertible convertible = value as IConvertible;

    if (convertible == null)
    {
        return false;
    }

    return true;
}