OC基础之NSCharacterSet---iOS笔记摘录

目录
  1. NSCharacterSet
  2. NSMutableCharacterSet

水滴石穿 铁杵成针

前言

1. 可用于删除字符串的指定字符

1. NSCharacterSet

NSCharacterSet : NSObject <NSCopying, NSMutableCopying, NSSecureCoding>

1. characterSetWithCharactersInString

// 根据字符串生成一个NSCharacterSet对象
// 可用于componentsSeparatedByCharactersInSet分割字符串,以该字符串所有单个字符为分隔符
NSCharacterSet *characterSet=[NSCharacterSet characterSetWithCharactersInString:@"He"];

// 取反
NSCharacterSet *characterInvertSet=[characterSet invertedSet];

例1（删除字符串"Hello World!hello NSCharacterSet!"中的H、e）

    NSString *str=@"Hello World!hello NSCharacterSet!";

    //
    NSCharacterSet *characterSet=[NSCharacterSet characterSetWithCharactersInString:@"He"];
    // 先以H、e将字符串分割成数组，然后再拼接
    NSString *resultStr=[[str componentsSeparatedByCharactersInSet:characterSet]componentsJoinedByString:@""];
    // llo World!hllo NSCharactrSt!
    NSLog(@"%@",resultStr);

2. invertedSet

// 以相反的字符串进行分割，再拼接
NSCharacterSet *characterInvertSet=[characterSet invertedSet];

例1

    // 以相反的字符串进行分割，再拼接
    NSCharacterSet *characterInvertSet=[characterSet invertedSet];
    NSString *resultInvertStr=[[str componentsSeparatedByCharactersInSet:characterInvertSet]componentsJoinedByString:@""];
    // Heeee
    NSLog(@"%@",resultInvertStr);

3. 快捷NSCharacterSet

// 空格
NSCharacterSet *characterSet=[NSCharacterSet whitespaceCharacterSet];

常用

    whitespaceCharacterSet              // 空格
    newlineCharacterSet                 // 换行
    whitespaceAndNewlineCharacterSet    // 空格和换行
    decimalDigitCharacterSet            // 0-9的数字
    letterCharacterSet                  // 所有字母
    lowercaseLetterCharacterSet         // 小写字母
    uppercaseLetterCharacterSet         // 大写字母
    alphanumericCharacterSet            // 所有数字和字母（大小写不分）
    punctuationCharacterSet             // 标点符号

    controlCharacterSet
    nonBaseCharacterSet
    alphanumericCharacterSet
    decomposableCharacterSet
    illegalCharacterSet
    capitalizedLetterCharacterSet
    symbolCharacterSet

2. NSMutableCharacterSet

NSMutableCharacterSet : NSCharacterSet <NSCopying, NSMutableCopying, NSSecureCoding>

1. addCharactersInString、removeCharactersInString

// 添加字符
[muSet addCharactersInString:@"o"];
// 删除字符
[muSet removeCharactersInString:@"H"];

例1

    NSString *str=@"Hello World!hello NSCharacterSet!";

    NSMutableCharacterSet *muSet=[NSMutableCharacterSet characterSetWithCharactersInString:@"He"];
    [muSet addCharactersInString:@"o"];
    [muSet removeCharactersInString:@"H"];
    NSString *resultTStr=[[str componentsSeparatedByCharactersInSet:muSet]componentsJoinedByString:@""];
    // Hll Wrld!hll NSCharactrSt!
    NSLog(@"%@",resultTStr);

2. invert

注意：这个方法没有返回值

// 以相反的字符串进行分割，再拼接
[muSet invert];

例1

    NSMutableCharacterSet *muSet=[NSMutableCharacterSet characterSetWithCharactersInString:@"He"];
    [muSet invert];
    NSString *resultTStr=[[str componentsSeparatedByCharactersInSet:muSet]componentsJoinedByString:@""];
    // Heeee
    NSLog(@"%@",resultTStr);