A9E14108DF763789CB80A64656CBD343.png

由上面的结果可知0是最宽，1最窄，但是排序的话如果一个一个去排，虽然也能完成，但是太累了，身为程序员，一定要让程序为我们服务。

NSMutableDictionary* dic = [NSMutableDictionary dictionaryWithCapacity:0];
for (NSInteger i = 0; i < 10; i++) {
  NSString* valueString = [NSString stringWithFormat:@"%@",@(i)];
  CGFloat width = [AppDelegate calculateTextLength:IS_FONT(20) givenText:valueString];
  [dic setObject:valueString forKey:@(width)];
}
NSArray *keyArr = dic.allKeys;
NSArray *ascendingArr = [keyArr sortedArrayUsingComparator:^NSComparisonResult(id  _Nonnull obj1, id  _Nonnull obj2) {
  if ([obj1 floatValue] > [obj2 floatValue]) {
    return NSOrderedAscending;
  } else if ([obj1 floatValue] == [obj2 floatValue]) {
    return NSOrderedSame;
  } else {
    return NSOrderedDescending;
  }
}];
for (NSInteger i = 0; i<ascendingArr.count; i++) {
  NSNumber *key = ascendingArr[i];
  NSLog(@"--->i:%@ ---->width:%@\n",dic[key], key);
}

2018-08-03 17:06:00.002609+0800 ISBaseDemo[4122:423885] --->i:0 ---->width:13.490234375
2018-08-03 17:06:00.002670+0800 ISBaseDemo[4122:423885] --->i:4 ---->width:13.451171875
2018-08-03 17:06:00.002697+0800 ISBaseDemo[4122:423885] --->i:8 ---->width:13.34375
2018-08-03 17:06:00.002721+0800 ISBaseDemo[4122:423885] --->i:9 ---->width:13.333984375
2018-08-03 17:06:00.002745+0800 ISBaseDemo[4122:423885] --->i:3 ---->width:13.197265625
2018-08-03 17:06:00.002769+0800 ISBaseDemo[4122:423885] --->i:5 ---->width:13.060546875
2018-08-03 17:06:00.002793+0800 ISBaseDemo[4122:423885] --->i:2 ---->width:12.6796875
2018-08-03 17:06:00.002819+0800 ISBaseDemo[4122:423885] --->i:7 ---->width:12.298828125
2018-08-03 17:06:00.002843+0800 ISBaseDemo[4122:423885] --->i:1 ---->width:10.228515625

由此可知，字符宽度由高到低依次是：0，4，8，9，3，5，2，7，1.

附：

+ (CGFloat)calculateTextLength:(UIFont*)font givenText:(NSString*)text {
  NSDictionary* attribute = @{NSFontAttributeName : font};
  CGSize titleSize =
  [text boundingRectWithSize:CGSizeMake(MAXFLOAT, 0)
                     options:NSStringDrawingTruncatesLastVisibleLine |
   NSStringDrawingUsesLineFragmentOrigin |
   NSStringDrawingUsesFontLeading
                  attributes:attribute
                     context:nil]
  .size;
  CGFloat length = titleSize.width + 1.0f;
  
  return length;
}