Convert object to array type [duplicate]

Question

I am passing an array as an object in a web method.How can I convert object to an array in web method

public static string sample(object arr)
{
    string[] res= (string[])arr; //convertion object to string array
    return "";
}

I getting error like this

An exception of type 'System.InvalidCastException' occurred in Flair.dll but was not handled in user code

Answer 1

Simplest method:

public static string[] Convert(object input)
{
  return input as string[];
}

But You have to validate input if you can cast that way, or cast to array of objects and call ToString() on each element

Answer 2

When you downcast you need to check :

public static string sample(object arr)
{
    string[] res=   arr as string[];  
   if (res!=null)
       {
            //ok to continue
       }
   else
      {
         //arr is not string[]
      }
    return "";
}

Try to avoid (string[])arr unless you're 100% sure that arr is string[]