iOS *格式化，344格式

1 @interface ViewController ()<UITextFieldDelegate>
2 {
3     NSString    *previousTextFieldContent;
4     UITextRange *previousSelection;
5 }
6 @end

1 - (void)viewDidLoad
2 {
3     [super viewDidLoad];
4     // Do any additional setup after loading the view, typically from a nib.
5     self.textField.delegate = self;
6     [self.textField addTarget:self action:@selector(formatPhoneNumber:) forControlEvents:UIControlEventEditingChanged];
7 }

  1 - (void)formatPhoneNumber:(UITextField*)textField
  2 {
  3     NSUInteger targetCursorPosition =
  4     [textField offsetFromPosition:textField.beginningOfDocument
  5                        toPosition:textField.selectedTextRange.start];
  6     NSLog(@"targetCursorPosition:%li", (long)targetCursorPosition);
  7     // nStr表示不带空格的号码
  8     NSString* nStr = [textField.text stringByReplacingOccurrencesOfString:@" " withString:@""];
  9     NSString* preTxt = [previousTextFieldContent stringByReplacingOccurrencesOfString:@" "
 10                                                                            withString:@""];
 11     
 12     char editFlag = 0;// 正在执行删除操作时为0，否则为1
 13     
 14     if (nStr.length <= preTxt.length) {
 15         editFlag = 0;
 16     }
 17     else {
 18         editFlag = 1;
 19     }
 20     
 21     // textField设置text
 22     if (nStr.length > 11)
 23     {
 24         textField.text = previousTextFieldContent;
 25         textField.selectedTextRange = previousSelection;
 26         return;
 27     }
 28     
 29     // 空格
 30     NSString* spaceStr = @" ";
 31     
 32     NSMutableString* mStrTemp = [NSMutableString new];
 33     int spaceCount = 0;
 34     if (nStr.length < 3 && nStr.length > -1)
 35     {
 36         spaceCount = 0;
 37     }else if (nStr.length < 7 && nStr.length >2)
 38     {
 39         spaceCount = 1;
 40         
 41     }else if (nStr.length < 12 && nStr.length > 6)
 42     {
 43         spaceCount = 2;
 44     }
 45     
 46     for (int i = 0; i < spaceCount; i++)
 47     {
 48         if (i == 0) {
 49             [mStrTemp appendFormat:@"%@%@", [nStr substringWithRange:NSMakeRange(0, 3)], spaceStr];
 50         }else if (i == 1)
 51         {
 52             [mStrTemp appendFormat:@"%@%@", [nStr substringWithRange:NSMakeRange(3, 4)], spaceStr];
 53         }else if (i == 2)
 54         {
 55             [mStrTemp appendFormat:@"%@%@", [nStr substringWithRange:NSMakeRange(7, 4)], spaceStr];
 56         }
 57     }
 58     
 59     if (nStr.length == 11)
 60     {
 61         [mStrTemp appendFormat:@"%@%@", [nStr substringWithRange:NSMakeRange(7, 4)], spaceStr];
 62     }
 63     
 64     if (nStr.length < 4)
 65     {
 66         [mStrTemp appendString:[nStr substringWithRange:NSMakeRange(nStr.length-nStr.length % 3,
 67                                                                     nStr.length % 3)]];
 68     }else if(nStr.length > 3)
 69     {
 70         NSString *str = [nStr substringFromIndex:3];
 71         [mStrTemp appendString:[str substringWithRange:NSMakeRange(str.length-str.length % 4,
 72                                                                    str.length % 4)]];
 73         if (nStr.length == 11)
 74         {
 75             [mStrTemp deleteCharactersInRange:NSMakeRange(13, 1)];
 76         }
 77     }
 78     NSLog(@"=======mstrTemp=%@",mStrTemp);
 79     
 80     textField.text = mStrTemp;
 81     // textField设置selectedTextRange
 82     NSUInteger curTargetCursorPosition = targetCursorPosition;// 当前光标的偏移位置
 83     if (editFlag == 0)
 84     {
 85         //删除
 86         if (targetCursorPosition == 9 || targetCursorPosition == 4)
 87         {
 88             curTargetCursorPosition = targetCursorPosition - 1;
 89         }
 90     }
 91     else {
 92         //添加
 93         if (nStr.length == 8 || nStr.length == 3)
 94         {
 95             curTargetCursorPosition = targetCursorPosition + 1;
 96         }
 97     }
 98 
 99     UITextPosition *targetPosition = [textField positionFromPosition:[textField beginningOfDocument]
100                                                               offset:curTargetCursorPosition];
101     [textField setSelectedTextRange:[textField textRangeFromPosition:targetPosition
102                                                          toPosition :targetPosition]];
103 }
104 
105 - (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
106 {
107     previousTextFieldContent = textField.text;
108     previousSelection = textField.selectedTextRange;
109     
110     return YES;
111 }

相关阅读:
(转载)Linux进程基础
 C语言字符串
 DNS域名解析服务
 Linux-SSH远程管理
 Linux文件系统深入了解
 Linux进程和计划任务管理
 Linux账户与权限管理
 MySQL实现读写分离
 SQL数据库常用函数
 MySQL进阶查询（二）
原文地址：https://www.cnblogs.com/farer-zcz/p/4081505.html