IOS - Unicode Unsign

Question

I have a function written in C#, i want to convert it to objective-c. How to do it?

public static string UnicodeUnSign(string s)
{
    const string uniChars = "àáảãạâầấẩẫậăằắẳẵặèéẻẽẹêềếểễệđìíỉĩịòóỏõọôồốổỗộơờớởỡợùúủũụưừứửữựỳýỷỹỵÀÁẢÃẠÂẦẤẨẪẬĂẰẮẲẴẶÈÉẺẼẸÊỀẾỂỄỆĐÌÍỈĨỊÒÓỎÕỌÔỒỐỔỖỘƠỜỚỞỠỢÙÚỦŨỤƯỪỨỬỮỰỲÝỶỸỴÂĂĐÔƠƯ";
    const string koDauChars = "aaaaaaaaaaaaaaaaaeeeeeeeeeeediiiiiooooooooooooooooouuuuuuuuuuuyyyyyAAAAAAAAAAAAAAAAAEEEEEEEEEEEDIIIOOOOOOOOOOOOOOOOOOOUUUUUUUUUUUYYYYYAADOOU";

    if (string.IsNullOrEmpty(s))
    {
        return s;
    }

    string retVal = String.Empty;
    for (int i = 0; i < s.Length; i++)
    {
        int pos = uniChars.IndexOf(s[i].ToString());
        if (pos >= 0)
            retVal += koDauChars[pos];
        else
            retVal += s[i];
    }
    return retVal;
}

Answer 1

You could use the CoreFoundation CFStringTransform function which does almost all transformations from your list. Only "đ" and "Đ" have to be handled separately:

NSString *UnicodeUnsign(NSString *s)
{
    NSMutableString *result = [s mutableCopy];
    // __bridge only required if you compile with ARC:
    CFStringTransform((__bridge CFMutableStringRef)result, NULL, kCFStringTransformStripCombiningMarks, NO);

    [result replaceOccurrencesOfString:@"đ" withString:@"d" options:0 range:NSMakeRange(0, [result length])];
    [result replaceOccurrencesOfString:@"Đ" withString:@"D" options:0 range:NSMakeRange(0, [result length])];

    return result;
}

Example:

NSString *input = @"Hễllö Wõrld! - ếểễệđìíỉĩịòó";
NSString *output = UnicodeUnsign(input);
NSLog(@"%@", output);
// Output: Hello World! - eeeediiiiioo