这里会归纳一些在Objective-C开发中常用的代码 代码会慢慢增多  =）

生成一定范围的随机数

Objective-C

-(float)RandomFloatStart:(float)a end:(float)b {
        srand((unsigned)time(0));
        float random = ((float) rand()) / (float) RAND_MAX;
        float diff = b - a;
        float r = random * diff;
        return a + r;
}

验证邮箱是否合法

- (BOOL) validEmail:(NSString*) emailString {
      if([emailString length]==0){
         return NO;
      }

      NSString *regExPattern = @"[A-Z0-9a-z._%+-][email protected][A-Za-z0-9.-]+\\.[A-Za-z]{2,4}";

      NSRegularExpression *regEx = [[NSRegularExpression alloc] initWithPattern:regExPattern       options:NSRegularExpressionCaseInsensitive error:nil];
      NSUInteger regExMatches = [regEx numberOfMatchesInString:emailString options:0 range:NSMakeRange(0, [emailString length])];

      NSLog(@"%i", regExMatches);
      if (regExMatches == 0) {
          return NO;
      } else {
          return YES;
      }
}

判断手机是否越狱

+(BOOL)isJailbroken {
      NSString *filePath = @"/Applications/Cydia.app";
      if ([[NSFileManager defaultManager] fileExistsAtPath:filePath])
      {
            return YES;
      } else {
            return NO;
      }
}

or

+(BOOL)isJailbroken {
      FILE *f = fopen("/bin/bash", "r");
      BOOL isbash = NO;
      if (f != NULL) {
            //Device is jailbroken
            isbash = YES;
      }
      fclose(f);
}