IOS笔记之可变字符串NSMutableString是NSString的子类。

NSMutableString是NSString的子类。

1.追加字符串

NSMutableString *str = [[NSMutableString alloc] initWithCapacity:10];
[str setString:@"Hello"];

[str appendString:@" World"];
NSLog(@"str = %@",str);
[str appendFormat:@"- %d",10];
NSLog(@"str= %@",str);

2.替换字符串

NSRange range = [str rangeOfString:@"World"];
[str replaceCharactersInRange:range withString:@"IOS"];
NSLog(@"str =%@",str);

3.插入字符串

[str insertString:@" android " atIndex:6];
NSLog(@"str = %@",str);

4.删除字符串

NSRange range1 = [str rangeOfString:@"Hello"];
[str deleteCharactersInRange:range1];
NSLog(@"str = %@",str);