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ref、out 关键字

    class ParameterTest    {        static void Main(string[] args)        {            int i = 0;            int[] ints = { 0, 1, 2, 4, 8 };            Console.WriteLine("i = " + i);            Console.WriteLine("ints[0] = " + ints[0]);            SomeFunction(ints,i);            Console.WriteLine("i = " + i);            Console.WriteLine("ints[0] = " + ints[0]);            Console.ReadKey();        }        static void SomeFunction(int[] ints,int i)        {            ints[0] = 100;            i = 100;        }    }

    class ParameterTest    {        static void Main(string[] args)        {            int i = 0;            int[] ints = { 0, 1, 2, 4, 8 };            Console.WriteLine("i = " + i);            Console.WriteLine("ints[0] = " + ints[0]);            SomeFunction(ints,ref i);            Console.WriteLine("i = " + i);            Console.WriteLine("ints[0] = " + ints[0]);            Console.ReadKey();        }        static void SomeFunction(int[] ints,ref int i)        {            ints[0] = 100;            i = 100;        }    }

 如果把一个参数传递给方法,且这个方法的输入参数钱带有ref关键字,则改方法对变量所做的任何改变都会影响原始对象的值。

    class OutTest    {        static void Main(string[] args)        {            int i;            SomeFunction(out i);            Console.WriteLine(i);            Console.ReadKey();        }        static void SomeFunction(out int i)        {            i = 100;        }    }
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变量如果未赋初始值而是用肯定会报错,而是用Out关键字之后可以解决这一问题

ref、out 关键字