iOStextField/textView在输入时限制emoji表情的输入

https://www.jianshu.com/p/5227e6aab4d4

2017.02.27 13:08* 字数 146 阅读 6109评论 6喜欢 14

又遇到输入框输入表情的情况了，之前写了一篇文章“UITextView/UITextField检测并过滤Emoji表情符号”http://www.jianshu.com/p/90d68e7e5d53,但是总觉得那两种方式都各有弊端，这次又遇到之后，仔细考虑了下之后，想到了用两种方式组合在一起使用，测试结果暂时没什么问题，在输入时就限制了emoji表情输入，完全符合需求。在此贴出代码，如果有什么问题，欢迎指正！

@interface JQTestViewController ()<UITextFieldDelegate>

@property (weak, nonatomic) IBOutlet UITextField *textField;

@property (nonatomic, assign) NSInteger textLocation;//这里声明一个全局属性，用来记录输入位置

@end

- (void)viewDidLoad {

[super viewDidLoad];

self.textField.delegate = self;

[self.textField addTarget:self action:@selector(textFieldDidChanged:) forControlEvents:UIControlEventEditingChanged];//注意：textFied没有textFieldDidChanged代理方法，但是有UITextFieldTextDidChangeNotification通知，这里添加通知方法，textView有textFieldDidChanged代理方法，下面用法一样

}

#pragma mark-- UITextFieldDelegate

//在输入时，调用下面那个方法来判断输入的字符串是否含有表情

- (void)textFieldDidChanged:(UITextField *)textField

{

if (textField.text.length > 20) {

textField.text = [textField.text substringToIndex:20];

[self showMessage:@"不可超过20字！"];

}else {

if (self.textLocation == -1) {

NSLog(@"输入不含emoji表情");

}else {

NSLog(@"输入含emoji表情");

//截取emoji表情前

textField.text = [textField.text substringToIndex:self.textLocation];

}

}

}

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string

{

NSLog(@"location-->>%lu",(unsigned long)range.location);

NSLog(@"replacementString-->>%@",string);

//禁止输入emoji表情

if ([self stringContainsEmoji:string]) {

self.textLocation = range.location;

}else {

self.textLocation = -1;

}

return YES;

}

//表情符号的判断

- (BOOL)stringContainsEmoji:(NSString *)string {

__block BOOL returnValue = NO;

[string enumerateSubstringsInRange:NSMakeRange(0, [string length])

options:NSStringEnumerationByComposedCharacterSequences

usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {

const unichar hs = [substring characterAtIndex:0];

if (0xd800 <= hs && hs <= 0xdbff) {

if (substring.length > 1) {

const unichar ls = [substring characterAtIndex:1];

const int uc = ((hs - 0xd800) * 0x400) + (ls - 0xdc00) + 0x10000;

if (0x1d000 <= uc && uc <= 0x1f77f) {

returnValue = YES;

}

}

} else if (substring.length > 1) {

const unichar ls = [substring characterAtIndex:1];

if (ls == 0x20e3) {

returnValue = YES;

}

} else {

if (0x2100 <= hs && hs <= 0x27ff) {

returnValue = YES;

} else if (0x2B05 <= hs && hs <= 0x2b07) {

returnValue = YES;

} else if (0x2934 <= hs && hs <= 0x2935) {

returnValue = YES;

} else if (0x3297 <= hs && hs <= 0x3299) {

returnValue = YES;

} else if (hs == 0xa9 || hs == 0xae || hs == 0x303d || hs == 0x3030 || hs == 0x2b55 || hs == 0x2b1c || hs == 0x2b1b || hs == 0x2b50) {

returnValue = YES;

}

}

}];

return returnValue;

}