CODEWITHSUNDEEP
c#string
virii
virii

Reputation: 73

Convert a string to a datatype base on a string that contains datatype name

I am converting a string to a datatype based on the another string that contains the name of datatype. I have two string like below:

string string_1 = "true";

string string_2 = "System.Boolean";

i need to convert the string 1 to the data type that is specified in string 2. how can i do that?(note that the string_2 can be each datatype) must i use if's for checking string_2 with any type of datatype?

Upvotes: 1

Views: 92

Answers (2)

Patrik
Patrik

Reputation: 1382

For the given type ChangeType works well:

Convert.ChangeType(string_1, Type.GetType(string_2))

But if you have different types, like an own class, this won't work. In that case, there is no such generic way, since the framework cannot now how to parse a value. If you try, you will get a InvalidCastException. In that case, you can only hand-write a converter. In the special case, you have - beside primitives - only own classes, you could consider using a static-conversion method in each class for the job. Would probably look like this:

Type.GetType(string_2).GetMethod("convert").Invoke(string_1)

Anyway, no nice solution here. IMHO, the hand-written conversion (doing it with ifs) is the only proper way.

Upvotes: 1

haim770
haim770

Reputation: 49133

Assuming the target type is a primitive that is either Convertible or Parseable, you can try the following:

object result;
string string_1 = "true";
string string_2 = "System.Boolean";

var targetType = Type.GetType(string_2);

if (typeof(IConvertible).IsAssignableFrom(targetType))
{
    result = Convert.ChangeType(string_1, targetType);
}
else
{
    var parseMethod = targetType.GetMethod("Parse", new[] {typeof (string)});

    if (parseMethod != null)
        result = parseMethod.Invoke(null, new object[] { string_1 });
}

See ChangeType

Upvotes: 1

Related Questions