NSCharacterSet简介
1 | /** 根据一个给定的字符串获取一个NSCharacterSet对象 */ |
使用方式
1 | NSCharacterSet *set = [NSCharacterSet characterSetWithCharactersInString:@"0123456789"]; |
打印结果
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12 2019-02-15 10:32:39.850440+0800 Tips[60524:1826221] set----(
"",
"",
af,
"",
""
)
2019-02-15 10:32:39.850576+0800 Tips[60524:1826221] invertedSet----(
67,
"",
34
)
NSMutableCharacterSet
用法同NSCharacterSet,但是 invert 属性没有返回值
1 | NSMutableCharacterSet *set1 = [NSMutableCharacterSet characterSetWithCharactersInString:@"Hell"]; |
问题:如何限制UITextField输入数字
1 | - (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string { |