重学CSharp（三）

今天，简单的说一下params这个关键字，params 关键字可以指定在参数数目可变处采用参数的方法参数。在方法声明中的 params 关键字之后不允许任何其他参数，并且在方法声明中只允许一个 params 关键字。下面来看个例子：
        using System;

        class TestApp
       {
             static double CalculateAverage(params double[] values)//这里用了params
             {
                 double sum = 0;
                 for(int i = 0; i < values.Length; i++)
                 {
                     sum += values[i];
                 }
                 return (sum/values.Length);
             }
             static void Main(string[] args)
             {
                 double average;
                 average = CalculateAverage(4.0, 3.2, 5.7);
                 Console.WriteLine("Average of 4.0, 3.2, 5.7 is: {0}",average);
                 double[] data = {4.0, 3.2, 5.7，6.0};
                 double ave;
                 ave = CalculateAverage(data);
                 Console.WriteLine("Average of data is: {0}",ave);
             }
        }