一、实现的逻辑很简单且代码量不多,直接贴出源码供方便快速使用。
@property (nonatomic, strong) UITextView *textView; @property (nonatomic, strong) UILabel *limitLabel; _textView = [[UITextView alloc] initWithFrame:CGRectMake(5, 5, MAIN_WIDTH-10, 130.3)]; _textView.placeHolder = @"请描述您的问题..."; _textView.returnKeyType = UIReturnKeyDone; _textView.delegate = self; _textView.textColor = UIColorFromRGB(0xBEBDBD); _textView.font = [UIFont systemFontOfSize:15]; [self addSubview:_textView]; _limitLabel = [[UILabel alloc] initWithFrame:CGRectMake(MAIN_WIDTH/4*3, 130.3, MAIN_WIDTH/4-10, 20)]; _limitLabel.text = @"0/500"; _limitLabel.font = [UIFont systemFontOfSize:12]; _limitLabel.textAlignment = NSTextAlignmentRight; _limitLabel.textColor = UIColorFromRGB(0x999999); _limitLabel.backgroundColor = [UIColor clearColor];
二、实现TextView代理方法
实时监听TextView输入框的return键,当点击return键时结束编辑的实现思路:判断输入的字是否为/n回车,即按下return键
- (void)textViewDidChange:(UITextView *)textView { _limitLabel.text = [NSString stringWithFormat:@"%ld/500",textView.text.length ]; } - (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text{ NSLog(@"textLength == %ld",textView.text.length); if ([text isEqualToString:@"/n"]){ //判断输入的字是否是回车,即按下return [self.textView resignFirstResponder]; return NO; } if ([self stringContainsEmoji:text] == YES) { [PubllicMaskViewHelper showTipViewWith:@"不支持输入Emoji表情符号" inSuperView:self withDuration:1]; return NO; } if (textView.text.length + text.length > 500) { NSString *allText = [NSString stringWithFormat:@"%@%@",textView.text,text]; textView.text = [allText substringToIndex:500]; [PubllicMaskViewHelper showTipViewWith:@"输入不能超过500个字" inSuperView:self withDuration:1]; return NO; } return YES; }
三、过滤所有Emoji表情符号
// 过滤所有表情 - (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]; // surrogate pair if (0xd800 <= hs && hs 1) { const unichar ls = [substring characterAtIndex:1]; const int uc = ((hs - 0xd800) * 0x400) + (ls - 0xdc00) + 0x10000; if (0x1d000 <= uc && uc 1) { const unichar ls = [substring characterAtIndex:1]; if (ls == 0x20e3) { returnValue = YES; } } else { // non surrogate 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; }