procedure TFormMain.BBtnCheckMd5Click(Sender: TObject);
var
md5:IdHashMessageDigest.TIdHashMessageDigest5;
s:String;
w:widestring;
begin
md5:=IdHashMessageDigest.TIdHashMessageDigest5.Create;
w:=utf8decode(Mdata.Lines.Text);

s:=md5.AsHex( md5.HashValue( w ) ); //会不会自动又被转为ansistring了。。。
md5.Free;
if uppercase(s)<>uppercase(trim(Emd5.Text)) then
unitdialog.Badbox('数字签名核对失败！')
else
unitdialog.Badbox('数字签名核对一致！');
end;