OC之NSString常用方法

 1 #import <Foundation/Foundation.h>
 2 
 3 int main(int argc, const char * argv[])
 4 {
 5     @autoreleasepool
 6     {
 7         /*
 8         NSString *beijing = @"北京";
 9         NSString *welcome = [beijing stringByAppendingString:@"  欢迎你 "];//字符串连接
10         NSLog(@"%@",welcome);
11         NSLog(@"%zi",welcome.length);//字符串的长度
12         BOOL flag = [beijing isEqualToString:@"北京"];//字符串比较
13         NSLog(@"%d",flag);
14          */
15         /*
16         NSString *number = @"123456",*floatNumber = @"1233.45";
17         float aa = [floatNumber floatValue];// 字符串转换成浮点型
18         int  a = [number intValue];//字符串转换成整型
19         NSLog(@"%d,%f",a,aa);
20         */
21        /*
22         NSString *seachStr = @"12345.doc";
23         BOOL f =  [seachStr hasPrefix:@"123"];//判断A字符串是否以B字符串为开头
24         BOOL f1 = [seachStr hasSuffix:@".doc"];//判断A字符串是否以B字符串结尾
25         NSRange range = [seachStr rangeOfString:@"234"];//搜索B字符串在A字符串中的范围
26  //库中的NSRange(包含了位置和长度的结构体)
27 //        typedef struct _NSRange {
28 //        NSUInteger location;
29 //        NSUInteger length;
30 //        } NSRange;
31         NSLog(@"%d,%d,%lu,%lu",f,f1,(range.location),(range.length));//位置  长度  (unsigned long)
32         
33         if (range.location == NSNotFound)
34         {
35             NSLog(@"没找到");
36         }*/
37         
38         /*
39         NSString *subResource = @"abcde";
40         NSString *subStr = [subResource substringFromIndex:3];//从位置1开始剪切字符串，包含1
41         NSLog(@"%@",subStr);
42         
43         NSString *subStr2 = [subResource substringToIndex:3];//剪切到位置3，不包含3，留下3
44         NSLog(@"%@",subStr2);
45          */
46         /*
47         NSString *subResource = @"abcde";
48         NSRange range1 = NSMakeRange(1, 2);
49 //        range1.location = 1;//位置
50 //        range1.length = 2;//长度
51 //等价
52 //库中的NSMakeRange
53 //        NS_INLINE NSRange NSMakeRange(NSUInteger loc, NSUInteger len) {
54 //            NSRange r;
55 //            r.location = loc;
56 //            r.length = len;
57 //            return r;
58 //        }
59         NSString *subStr3 = [subResource substringWithRange:range1];//剪切给定范围的字符串
60         //compare方法：1.升序：前 < 后（-1），2.相等0  3.降序：前 > 后（1）
61         NSLog(@"%@",subStr3);*/
62         
63 //        NSLog(@"%d",(NSComparisonResult result = [@"ABC" compare:@"abc"]));
64         NSComparisonResult/*枚举类型*/ result = [@"abc" compare:@"abc" ] ;
65         NSLog(@"%ld",result);// NSOrderedAscending = -1L,存储类型L
66 //typedef NS_ENUM(NSInteger, NSComparisonResult) {NSOrderedAscending = -1L, NSOrderedSame, NSOrderedDescending};
67         
68         
69         
70     }
71     return 0;
72 }