A good algorithm for converting Arabic numerals into Chinese capitals

Capital | algorithm | chinese | convert//Add to Definition section of class
private static string[] cstr={"0", "one", "II", "three", "Restaurant", "WU", "Lu", "Qi", "ba", "Nine"};
private static string[] wstr={"," "," "," "Bai", "Qian", "Million", "Pick Up", "Bai", "Qian", "billion", "Pick Up", "Bai", "Thousand"};
The number must be within a 12-bit integer string
Call mode such as: Label1.text=convertint ("numeric string");

public string Convertint (String str)
{
int LEN=STR. Length;
int i;
String Tmpstr,rstr;
Rstr= "";
for (i=1;i<=len;i++)
{
Tmpstr=str. Substring (len-i,1);
Rstr=string. Concat (Cstr[int32.parse (TMPSTR)]+wstr[i],rstr);
}
Rstr=rstr. Replace ("titbits", "Pick up");
Rstr=rstr. Replace ("0 pick Up", "0");
Rstr=rstr. Replace ("0 bai", "0");
Rstr=rstr. Replace ("0 thousand", "0");
Rstr=rstr. Replace ("0 million", "million");
for (i=1;i<=6;i++)
Rstr=rstr. Replace ("00", "0");
Rstr=rstr. Replace ("0 million", "0");
Rstr=rstr. Replace ("0 billion", "billion");
Rstr=rstr. Replace ("00", "0");
rstr+= "Round the whole";
return RSTR;
}