Compiler Error CS0445
Updated: March 2009
Cannot modify the result of an unboxing conversion
The result of an unboxing conversion is a temporary variable. The compiler prevents you from modifying such variables because any modification would go away when the temporary variable goes away. To fix this, use a new value-type variable to store the intermediate expression, and assign the value to the new variable.
The following code generates CS0455:
namespace ConsoleApplication1 { // CS0445.CS class UnboxingTest { public static void Main() { Point p; p.x = 1; p.y = 5; object obj = p; // Generates CS0445: ((Point)obj).x = 2; // Use the following lines instead. //Point p2; //p2 = (Point)obj; //p2.x = 2; //obj = p2; // Verify the change. //Console.WriteLine(((Point)obj).x); } } public struct Point { public int x; public int y; } }
