Conversion between hexadecimal notation

// Convert a hexadecimal character into a decimal number unsigned char cconvnumsdlg: btoh (char ch) {// 0-9if (CH> = '0' & Ch <= '9') Return (CH-'0 '); // 9-15if (CH> = 'A' & Ch <= 'F') Return (CH-'A' + 0xa ); // 9-15if (CH> = 'A' & Ch <= 'F') Return (CH-'A' + 0xa); Return (255 );} // convert the hexadecimal format to binary cstring cconvnumsdlg: hextobinary (cstring strhex) {int nlenth = strhex. getlength (); char * hex = new char [nlenth]; hex = strhex. getbuffer (0); cstring strbinary = ""; for (INT I = 0; I <nlenth; I ++) {// convert a hexadecimal number to a decimal char H = hex [nLenth-1-i]; Int J = btoh (h); cstring STR; Str. format ("% d", J); // convert the decimal format to 4 as the binary STR = decimaltobinary (STR); strbinary ++ = STR;} return strbinary ;} // convert binary to hexadecimal cstring cconvnumsdlg: binarytohex (cstring strbinary) {int nlength = strbinary. getlength (); cstring STR = strbinary; // when the number of digits is not a multiple of four, the switch (nlength % 4) {Case 0: break; Case 1: strbinary. format ("% d % s", 0, 0, STR); break; Case 2: strbinary. format ("% d % s", 0, STR); break; Case 3: strbinary. format ("% d % s", 0, STR); break; default: Return ""; break;} cstring strhex, str1; str1 = ""; nlength = strbinary. getlength (); For (INT I = 1; I <= (nlength/4); I ++) {// convert every four bits to a hexadecimal number STR = strbinary. left (4); cstring strdecimal = binarytodecimal (STR); int ndecimal = atoi (strdecimal. getbuffer (0); If (ndecimal <10) str1.format ("% d", ndecimal); else {char c = 'A' + (nDecimal-10 ); str1.format ("% C", c);} strhex + = str1; strbinary = strbinary. right (strbinary. getlength ()-Str. getlength () ;} return strhex;} // convert the decimal value to the binary cstring cconvnumsdlg: decimaltobinary (cstring strdecimal) {int ndecimal = atoi (strdecimal. getbuffer (0); int nyushu; // remainder int nshang; // operator cstring strbinary = ""; char buff [2]; cstring STR = ""; bool bcontinue = true; while (bcontinue) {nyushu = ndecimal % 2; nshang = ndecimal/2; sprintf (buff, "% d", nyushu); STR = strbinary; strbinary. format ("% S % s", buff, STR); ndecimal = nshang; If (nshang = 0) bcontinue = false;} return strbinary ;} // convert the binary value to the decimal cstring cconvnumsdlg: binarytodecimal (cstring strbinary) {int nlenth = strbinary. getlength (); char * binary = new char [nlenth]; binary = strbinary. getbuffer (0); int ndecimal = 0; For (INT I = 0; I <nlenth; I ++) {char H = binary [nLenth-1-i]; char STR [1]; STR [0] = H; Int J = atoi (STR); For (int K = 0; k <I; k ++) {J = J * 2 ;} ndecimal + = J;} cstring strdecimal; strdecimal. format ("% d", ndecimal); Return strdecimal ;}