c# - 可选参数与空参数方法和重载的构造函数

Question

简单来说，假设你有两种方法:

public static void WriteMessage() 
{
    Console.Write("Empty Parameter Function");
}



public static void WriteMessage(string data = "Some Data")
{
    Console.Write("Optional Parameter Function");
}

为什么如果不带任何参数调用 WriteMessage 函数，它会运行“空参数函数”？我理解方法重载，但为什么可选参数函数不运行，就好像空参数函数不存在一样，它会运行？

Answer 1

关于过载解决方案的以下几点，来自MSDN , 解释了这个决定:

If two candidates are judged to be equally good, preference goes to a candidate that does not have optional parameters for which arguments were omitted in the call. This is a consequence of a general preference in overload resolution for candidates that have fewer parameters.