OC开发之——分类应用(32)

一 概述

1. 给NSString增加一个类方法：计算某个字符串中阿拉伯数字的个数
2. 给NSString增加一个对象方法：计算当前字符串中阿拉伯数字的根数

二 应用代码

2.1 NSString+Number.h

#import <Foundation/Foundation.h>
@interface NSString (Number)
+(int)numberCountOfString:(NSString *)str;
-(int)numberCount;
@end

2.2 NSString+Number.m

#import "NSString+Number.h"

@implementation NSString (Number)
+(int)numberCountOfString:(NSString *)str
{
//    int count=0;
//    for (int i=0; i<str.length; i++) {
//        UniChar c=[str characterAtIndex:i];
//        if(c>='0'&&c<='9')
//        {
//            count++;
//        }
//    }
//    return count;
    return [str numberCount];
}
-(int)numberCount
{
    int count=0;
      for (int i=0; i<self.length; i++) {
          UniChar c=[self characterAtIndex:i];
          if(c>='0'&&c<='9')
          {
              count++;
          }
      }
      return count;
}
@end

2.3 main.m

#import <Foundation/Foundation.h>
#import "NSString+Number.h"
int main(int argc, const char * argv[]) {
    @autoreleasepool {
        // insert code here...
        int count=[NSString numberCountOfString:@"fafae2323256fgsgga"];
        NSLog(@"%d",count);
        int count2=[@"fafae2323256fgsgga" numberCount];
         NSLog(@"%d",count2);
    }
    return 0;
}