try catch里面try catch嵌套

try catch里能否内嵌try catch?答案是肯定的。但是等内层try catch出异常之后是个什么执行顺序呢?看下面代码

static void Main(string[] args)
        {
            try
            {
                Console.WriteLine("----------------------外层try------------------------------");
                errorMethod();               
            }
            catch (Exception ex)
            {
                Console.WriteLine("----------------------外层catch" + ex.Message + "------------------------------");
            }
            finally {
                Console.WriteLine("----------------------外层finally------------------------------");
            }

            Console.ReadKey();


        }

        private static void errorMethod()
        {           
            try
            {
                Console.WriteLine("----------------------内层try------------------------------");
                int i = 0;
                int a = 100/i;
            }
            catch (Exception ex)
            {
                Console.WriteLine("----------------------内层catch" + ex.Message + "------------------------------");
            }
            finally {
                Console.WriteLine("----------------------内层finally------------------------------");
            }
        }

内层catch处理了异常,所以没有执行外层catch。

咱们把内层的catch注释掉  再试下

static void Main(string[] args)
        {
            try
            {
                Console.WriteLine("----------------------外层try------------------------------");
                errorMethod();               
            }
            catch (Exception ex)
            {
                Console.WriteLine("----------------------外层catch" + ex.Message + "------------------------------");
            }
            finally {
                Console.WriteLine("----------------------外层finally------------------------------");
            }

            Console.ReadKey();


        }

        private static void errorMethod()
        {           
            try
            {
                Console.WriteLine("----------------------内层try------------------------------");
                int i = 0;
                int a = 100/i;
            }
            //catch (Exception ex)
            //{
            //    Console.WriteLine("----------------------内层catch" + ex.Message + "------------------------------");
            //}
            finally {
                Console.WriteLine("----------------------内层finally------------------------------");
            }
        }

很明显,外层catch捕获了异常。

总结:try catch嵌套,内层不能捕获时,会考虑外层内否捕获,内层能捕获,则外层catch不执行。

try
            {
                //A  
                try
                {
                    //B 
                }
                catch
                {
                    //C  
                }
                finally
                {
                    //D  
                }
                //E  
            }
            catch
            {
                //F
            }
            finally
            {
                //G
            }

上面的代码 执行顺序

抛出异常在:内层A,E处由外层catch块捕获,并执行外层finally  
抛出异常在:内层B处,且有一合适内层catch捕获,执行内层finally,后执行E处  
抛出异常在:内层B处,但内层catch块没有合适处理程序,执行内层finally,搜索外层catch,找合适的,执行外层finally,此时不会执行E  
抛出异常在:内层C处,退出内层catch块,执行内层finally,搜索外层catch,找到合适,执行外层finally  
 抛出异常在:内层D处,退出内层finally块,搜索外层catch,找到合适,执行外层finally  

A抛异常 A=》F=》G

B抛异常 C能捕获 B=》C=》D=》E=》F=》G (若C处无法捕获B=》F=》G)

C抛异常 C=》D=》F=》G

D抛异常 D=》F=》G

E抛异常 A=》F=》G 同A

另外 try{}catch{} 中未做捕获类型限定,可捕获所以异常。如 try{}catch(IOException ex){} 则catch只能捕获I/O操作引发的异常。

暂无评论

发送评论 编辑评论


|´・ω・)ノ
ヾ(≧∇≦*)ゝ
(☆ω☆)
(╯‵□′)╯︵┴─┴
 ̄﹃ ̄
(/ω\)
∠( ᐛ 」∠)_
(๑•̀ㅁ•́ฅ)
→_→
୧(๑•̀⌄•́๑)૭
٩(ˊᗜˋ*)و
(ノ°ο°)ノ
(´இ皿இ`)
⌇●﹏●⌇
(ฅ´ω`ฅ)
(╯°A°)╯︵○○○
φ( ̄∇ ̄o)
ヾ(´・ ・`。)ノ"
( ง ᵒ̌皿ᵒ̌)ง⁼³₌₃
(ó﹏ò。)
Σ(っ °Д °;)っ
( ,,´・ω・)ノ"(´っω・`。)
╮(╯▽╰)╭
o(*////▽////*)q
>﹏<
( ๑´•ω•) "(ㆆᴗㆆ)
😂
😀
😅
😊
🙂
🙃
😌
😍
😘
😜
😝
😏
😒
🙄
😳
😡
😔
😫
😱
😭
💩
👻
🙌
🖕
👍
👫
👬
👭
🌚
🌝
🙈
💊
😶
🙏
🍦
🍉
😣
Source: github.com/k4yt3x/flowerhd
颜文字
Emoji
小恐龙
花!
上一篇
下一篇