GSM规范中的部分编码转换

在做跟手机短信相关的东东时候常遇到各种编码格式数据的转换，特写了几个函数，供参考。

function EncodeEnglish(var s:string):string;

var

i,j,len:Integer;

cur:Integer;

t:String;

begin

Result:='';

len:=Length(s);

//j 用于移位计数

i:=1;j:=0;

while i<=len do

begin

if i<len then

//数据变换

cur:=(ord(s[i]) shr j) or ((ord(s[i+1]) shl (7-j)) and $ff)

else

cur:=(ord(s[i]) shr j) and $7f;

FmtStr(t,'％2.2X',[cur]);

Result:=Result+t;

inc(i);

//移位计数达到7位的特别处理

j:=(j+1) mod 7;

if j=0 then inc(i);

end;

end;

//end;

function BinaryUniCode2Gb2312(ABinaryString:PChar;APosStart,APosEnd:integer):string;

var

i,iLen:integer;

AscHexText,TmpHexStr:string;

AsciiInt:integer ;

AscLen,AscUniLen:integer;

UniHexstr,GB2312:string;

begin

iLen:=Length(ABinaryString);

for i:= APosStart-1 to APosEnd-1 do

begin

AsciiInt:=ord(ABinaryString[i]);

TmpHexStr:=Format('%x',[AsciiInt]);

if length(TmpHexStr)=1 then

TmpHexStr:='0'+TmpHexStr;

AscHexText:=AscHexText+TmpHexStr;

end; //for

AscLen:=Length(AscHexText);

AscUniLen:=AscLen div 4;

for i:=0 to AscUniLen-1 do

begin

UniHexstr:=Copy(AscHexText,i*4+1,4);

// Gb2312 := Gb2312 + UnicodeToGb2312(HexAscii2DecimalInt(uniHexstr));

end; // for

result := Gb2312 ;

end;

function WideStringToUnicode_Ex(s:WideString;ADestStr:PChar;Limit:integer):integer;

var sLen:integer;

buffer:array[1..1024] of char;

tmpchar:char;

i:integer;

begin

sLen:=Length(s);

if sLen>0 then

begin

CopyMemory(@buffer,Pointer(s),2*SLen);

for i:=0 to SLen-1 do

begin

tmpchar:=buffer[2*i+1];

buffer[2*i+1]:=buffer[2*i+2];

buffer[2*i+2]:=tmpchar;

end;

if SLen>Limit then

SLen:=Limit;

CopyMemory(ADestStr,@buffer,2*SLen);

result:=SLen*2;

result:=2*SLen;

end

else

begin

result:=0;

end;

end;