How to limit expansion?

Question

C++ / C#

Good morning.
There is an extension for all data types

public static Int32 ToInt32(this Object line)
{
  return Convert.ToInt32(line);
}

But I would like it to appear on types like String, Int, Double, etc., how can I do this?

Answer 1

This cannot be done, unfortunately.
I propose to make several similar methods in one class, one for each required type:

public class NumericExtensions
{
  public static Int32 ToInt32(this Double line)
  {
    return (Int32)line;
  }
  public static Int32 ToInt32(this float line)
  {
    return (Int32)line;
  }
  public static Int32 ToInt32(this String line)
  {
    var res;
    int.TryParse(line, out res);
    return res;
  }
  // ... для каждого нужного типа
}

Answer 2

You are expanding the base object, there is no way to do it. Only by creating different methods for the desired objects