C#中ref参数与out参数的区别
先贴代码
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Ref_and_Out_test
{
class Program
{
static void Main(string[] args)
{
int a =0; //若不初始化b会产生编译时错误。使用未初始化变量
int b = 1; //即使不初始化b也没有问题;
RefAndOut(ref a,out b);
Console.WriteLine("after RefAndOut method process");
Console.WriteLine("a={0},b={1}", a, b);
}
static void RefAndOut(ref int a,out int b)
{
//b = 1; //若此处不进行初始化,则try to print b这个语句无法执行
Console.WriteLine("before change ref a=0 and out b =1 value");
//try to print b:Console.WriteLine("a={0},b={1}", a, b);
Console.WriteLine("Now change the value,a to 123 ,b to 999");
a = 123;
b = 999; //若在方法内不对b赋值,则会出现编译时错误提醒必须对b赋值
&
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RT。先贴代码
C# code
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Value_Ref_test1
{
class Program
{
static void Main(string[] args)
{
point a = new point (10,10) ;
point b = a;
......