How Can I Convert Types at Runtime?

Question

My scenario should be simple... the type I want to convert FROM is ALWAYS 'string'. What I want to convert to... could be many things - ints, DateTimes, ... strings, etc.

This would be easy:

string valueToConvertFrom = "123";  int blah = Convert.ToInt32(valueToConvertFrom); 

However... I don't know (until runtime) that the value I need to convert to is an 'Int' (or whatever). I have tried this:

string valueToConvertFrom = "123";  Type convertToType = typeof(int);  object blah = Convert.ChangeType(valueToConvertFrom, convertToType); 

But that gives me the following error: "Object must implement IConvertible."

I don't want to have to do a switch statement and call "Convert.ToBlah" based on the type name... any suggestions?

Answer 1

the clean way to do it is using the a TypeConverter. you can get an instance of a type converter by calling the TypeDescriptor.GetConverter and then using the instance of the type converter to do the convertion. so something like this:

string valueToConvertFrom = "123";  Type convertToType = typeof(int);  TypeConverter tc =  TypeDescriptor.GetConverter(convertToType);               object blah =tc.ConvertFromString(valueToConvertFrom);