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+ (void)limitTextFieldLength:(UITextField *)textField maxLength:(NSInteger)maxLength {
    NSString *toBeString = textField.text;
    NSString *lang = [[textField textInputMode] primaryLanguage]; // 键盘输入模式
    if ([lang isEqualToString:@"zh-Hans"]) { // 简体中文输入，包括简体拼音，健体五笔，简体手写
        UITextRange *selectedRange = [textField markedTextRange];
        //获取高亮部分
        UITextPosition *position = [textField positionFromPosition:selectedRange.start offset:0];
        // 没有高亮选择的字，则对已输入的文字进行字数统计和限制
        if (!position) {
            if (toBeString.length > maxLength) {
                textField.text = [toBeString substringToIndex:maxLength];
            }
        } else {
            // 有高亮选择的字符串，则暂不对文字进行统计和限制
        }
    } else {
        // 中文输入法以外的直接对其统计限制即可，不考虑其他语种情况
        if (toBeString.length > maxLength) {
            textField.text = [toBeString substringToIndex:maxLength];
        }
    }
}

+ (void)limitTextViewLength:(UITextView *)textView maxLength:(NSInteger)maxLength {
    NSString *toBeString = textView.text;
    NSString *lang = [[textView textInputMode] primaryLanguage];
    if ([lang isEqualToString:@"zh-Hans"]) {
        UITextRange *selectedRange = [textView markedTextRange];
        UITextPosition *position = [textView positionFromPosition:selectedRange.start offset:0];
        if (!position) {
            if (toBeString.length > maxLength) {
                textView.text = [toBeString substringToIndex:maxLength];
            }
        }
    } else {
        if (toBeString.length > maxLength) {
            textView.text = [toBeString substringToIndex:maxLength];
        }
    }
}