1 // DivTest.h
2 // 异常的处理
3 //
4 // Created by ma c on 15/8/11.
5 // Copyright (c) 2015年. All rights reserved.
6 //
7
8 #import <Foundation/Foundation.h>
9
10 @interface DivTest : NSObject
11 @property(nonatomic,assign)CGFloat x;
12 @property(nonatomic,assign)CGFloat y;
13 @property(nonatomic,assign)CGFloat div;
14 -(id)initWithX:(CGFloat) m andY:(CGFloat) n;
15 -(void)print;
16 @end
// 上面为类的声明部分
//类的实现部分
1 // DivTest.m
2 // 异常的处理
3 //
4 // Created by ma c on 15/8/11.
5 // Copyright (c) 2015年. All rights reserved.
6 //
7
8 #import "DivTest.h"
9 #import "MyException.h"
10 @implementation DivTest
11 -(id)initWithX:(CGFloat) m andY:(CGFloat) n
12 {
13 MyException *me;
14 self = [super init];
15 if(self!=nil)
16 {
17 _x = m;
18 _y = n;
19 if(_y==0)
20 {//如果_y=0,说明除数为零了,抛出异常给调用者去处理
21 @throw me = [[MyException alloc]initWithName:@"MyException:" reason:@"除数为零了" userInfo:nil];
22 }
23 }
24 return self;
25 }
26 -(void)print
27 {
28 NSLog(@"div:%.2f",_x/_y);
29 }
30 @end
//异常的声明和定义部分
1 // MyException.h
2 // 异常的处理
3 //
4 // Created by ma c on 15/8/11.
5 // Copyright (c) 2015年. All rights reserved.
6 //
7
8 #import <Foundation/Foundation.h>
9
10 @interface MyException : NSException
11
12 @end
13
14
15 // MyException.m
16 // 异常的处理
17 //
18 // Created by ma c on 15/8/11.
19 // Copyright (c) 2015年 bjsxt. All rights reserved.
20 //
21
22 #import "MyException.h"
23
24 @implementation MyException
25
26 @end
//主函数中对异常的测试和处理
1 // main.m
2 // 异常的处理
3 //
4 // Created by ma c on 15/8/11.
5 // Copyright (c) 2015年. All rights reserved.
6 //
7
8 #import <Foundation/Foundation.h>
9 #import "DivTest.h"
10 #import "MyException.h"
11 int main(int argc, const char * argv[])
12 {
13 @autoreleasepool
14 {
15 DivTest *dt;
16 @try
17 { //检测除数为0的异常
18 dt = [[DivTest alloc]initWithX:4 andY:0];
19 }
20 @catch(MyException *e)
21 { //捕捉除数为零的异常
22 NSLog(@"MyException:%@",[e reason]);
23 }
24 @catch(NSException *e)
25 { //捕捉其他的异常
26 NSLog(@"Exception:%@",[e reason]);
27 }
28 @finally
29 { //一定要执行的代码块
30 [dt print];
31 }
32 }
33 return 0;
34 }