调用方法：
在输入框的代理方法中使用
- (void)textViewDidChange:(UITextView *)textView{
NSLog(@"text:%@",textView.text);
if (textView.text.length <= TEXT_MAXLENGTH) {
label2.text = [NSString stringWithFormat:@"您还可以输入%lu个文字",TEXT_MAXLENGTH-[textView.text length]];
}
//该判断用于联想输入
if (textView.text.length > TEXT_MAXLENGTH){
textView.text = [textView.text substringToIndex:TEXT_MAXLENGTH];
}
}
- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text{
//判断加上输入的字符，是否超过界限
NSString *string = [NSString stringWithFormat:@"%@%@", textView.text, text];
if (string.length > TEXT_MAXLENGTH){
return NO;
}
// 限制苹果系统输入法 禁止输入表情
if ([[[UITextInputMode currentInputMode]primaryLanguage] isEqualToString:@"emoji"]) {
return NO;
}
//禁止输入emoji表情
if ([LGToolMethods stringContainsEmoji:text]) {
return NO;
}
return YES;
}
//判断是否输入了emoji 表情
+ (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;
}else if (hs == 0x200d){
returnValue = YES;
}
}
}];
return returnValue;
}
