c#中break,continue,return,,goto,throw的区别-

1、c#中break,continue,return,goto,throw的区别(摘抄2010-08-18 16:17break 语句用于终止最近的封闭循环或它所在的switch 语句。控制传递给终止语句后面的语句(如果有的话。continue 语句将控制权传递给它所在的封闭迭代语句的下一次迭代。goto 语句将程序控制直接传递给标记语句。goto 的一个通常用法是将控制传递给特定的switch-case 标签或switch 语句中的默认标签。goto 语句还用于跳出深嵌套循环。return 语句终止它出现在其中的方法的执行并将控制返回给调用方法。它还可以返回一个可选值。如果方法为void 类型,

2、则可以省略return 语句。throw 语句用于发出在程序执行期间出现反常情况(异常的信号。通常throw 语句与try-catch 或try-finally 语句一起使用。当引发异常时,程序查找处理此异常的catch 语句。也可以用throw 语句重新引发已捕获的异常。-break 示例-在此例中,条件语句包含一个应该从 1 计数到100 的计数器;但break 语句在计数达到 4 后终止循环。/ statements_break.csusing System;class BreakTeststatic void Main(for (int i = 1; i = 100; i+if (i

3、= 5break;Console.WriteLine(i;输出1234-continue 示例-在此示例中,计数器最初是从 1 到10 进行计数,但通过将continue 语句与表达式(i 9 一起使用,跳过了continue 与for 循环体末尾之间的语句。/ statements_continue.csusing System;class ContinueTeststatic void Main(for (int i = 1; i = 10; i+if (i 9continue;Console.WriteLine(i;输出910-goto 示例1-下面的示例演示了goto 在switch

4、语句中的使用。/ statements_goto_switch.csusing System;class SwitchTeststatic void Main(Console.WriteLine(Coffee sizes: 1=Small 2=Medium 3=Large;Console.Write(Please enter your selection: ;string s = Console.ReadLine(;int n = int.Parse(s;int cost = 0;switch (ncase 1:cost += 25;break;case 2:cost += 25;goto c

5、ase 1;case 3:cost += 50;goto case 1;default:Console.WriteLine(Invalid selection.;break;if (cost != 0Console.WriteLine(Please insert 0 cents., cost;Console.WriteLine(Thank you for your business.;输入2示例输出Coffee sizes: 1=Small 2=Medium 3=LargePlease enter your selection: 2Please insert 50 cents.Thank yo

6、u for your business.-goto 示例2-下面的示例演示了使用goto 跳出嵌套循环。/ statements_goto.cs/ Nested search loopsusing System;public class GotoTest1static void Main(int x = 200, y = 4;int count = 0;string, array = new stringx, y;/ Initialize the array:for (int i = 0; i x; i+for (int j = 0; j y; j+arrayi, j = (+count.To

7、String(;/ Read input:Console.Write(Enter the number to search for: ;/ Input a string:string myNumber = Console.ReadLine(;/ Search:for (int i = 0; i x; i+for (int j = 0; j y; j+if (arrayi, j.Equals(myNumbergoto Found;Console.WriteLine(The number 0 was not found., myNumber;goto Finish;Found:Console.WriteLine(The number 0 is found., myNumber;Finish:Console.WriteLine(End of search.;输入44示例输出Enter the number to search for: 44The number 44 is found.End of search.-throw 示例-此例演示如何使用throw 语句引发异常。/ throw exampleusing System;public class ThrowTeststatic