iOS 字符操作

1、从某个字符串中取某个字符：

NSString *baseStr = @"0123456789abcdefghijklmnopqrstuvwxyz";NSInteger num = [self getRandomNumber:0 to:baseStr.length];unichar bChar =   [baseStr characterAtIndex:num];NSLog(@"%C", bChar);

2、字符转字符串：

NSString *a = [NSString stringWithCharacters:&bChar length:1];

或者

  result = [NSString stringWithFormat:@"%C", bChar];