_walletNameTextField = [[CommonTextField alloc] initWithText:nil placeHolder:NSLocalizedString(@"設定錢包名稱(不超過25個字元)", nil)];
    [_walletNameTextField addTarget:self action:@selector(textFiledDidChanged:) forControlEvents:UIControlEventEditingChanged];

- (void)textFiledDidChanged:(UITextField *)textField {
    if
 
 (kMaxNumber == 0)
        return;

    NSString *toBeString = textField.text;
    NSString *lang = [[textField textInputMode] primaryLanguage]; // 鍵盤輸入模式
    if ([lang isEqualToString:@"zh-Hans"]) {                      // 簡體中文輸入，包括簡體拼音，健體五筆，簡體手寫

        //判斷markedTextRange是不是為Nil，如果為Nil的話就說明你現在沒有未選中的字元，
 

        //可以計算文字長度。否則此時計算出來的字元長度可能不正確

        UITextRange *selectedRange = [textField markedTextRange];
        //獲取高亮部分(感覺輸入中文的時候才有)
        UITextPosition *position = [textField positionFromPosition:selectedRange.start offset:0];
        // 沒有高亮選擇的字，則對已輸入的文字進行字數統計和限制
        if (!position) {
            //中文和字元一起檢測  中文是兩個字元
 

            if ([toBeString getStringLenthOfBytes] > kMaxNumber) {
                textField.text = [toBeString subBytesOfstringToIndex:kMaxNumber];
            }
        }
    } else {
        if ([toBeString getStringLenthOfBytes] > kMaxNumber) {
            textField.text = [toBeString subBytesOfstringToIndex:kMaxNumber];
        }
    }
}

#define kMaxNumber 25

// NSString分類方法：
- (NSInteger)getStringLenthOfBytes {
    NSInteger length = 0;
    for (int i = 0; i < [self length]; i++) {
        //擷取字串中的每一個字元
        NSString *s = [self substringWithRange:NSMakeRange(i, 1)];
        if ([self validateChineseChar:s]) {
            length += 2;
        } else {
            length += 1;
        }
    }
    return length;
}

- (NSString *)subBytesOfstringToIndex:(NSInteger)index {
    NSInteger length = 0;

    NSInteger chineseNum = 0;
    NSInteger zifuNum = 0;

    for (int i = 0; i < [self length]; i++) {
        //擷取字串中的每一個字元
        NSString *s = [self substringWithRange:NSMakeRange(i, 1)];
        if ([self validateChineseChar:s]) {
            if (length + 2 > index) {
                return [self substringToIndex:chineseNum + zifuNum];
            }

            length += 2;

            chineseNum += 1;
        } else {
            if (length + 1 > index) {
                return [self substringToIndex:chineseNum + zifuNum];
            }
            length += 1;

            zifuNum += 1;
        }
    }
    return [self substringToIndex:index];
}

//檢測中文或者中文符號
- (BOOL)validateChineseChar:(NSString *)string {
    NSString *nameRegEx = @"[\\u0391-\\uFFE5]";
    if (![string isMatchesRegularExp:nameRegEx]) {
        return NO;
    }
    return YES;
}

//檢測中文
- (BOOL)validateChinese:(NSString *)string {
    NSString *nameRegEx = @"[\u4e00-\u9fa5]";
    if (![string isMatchesRegularExp:nameRegEx]) {
        return NO;
    }
    return YES;
}

- (BOOL)isMatchesRegularExp:(NSString *)regex {
    NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];
    return [predicate evaluateWithObject:self];
}