示例

// CS0191.cs
class MyClass
{
    public readonly int TestInt = 6;  // OK to assign to readonly field in declaration

    MyClass()
    {
        TestInt = 11; // OK to assign to readonly field in constructor
    }

    public void TestReadOnly()
    {
        TestInt = 19;                  // CS0191
    }

    public static void Main()
    {
    }
}