代码通过测试的
希望对你有用
//---------------------------------------------------
procedure TForm1.Button1Click(Sender: TObject);
var
MailTo:string;
begin
MailTo := 'mailto:lcy32@stinfo.net?subject=你好&body=你好';
if ShellExecute(GetDesktopWindow(), 'open', PChar(MailTo), nil, nil,
SW_SHOWNORMAL) <= 32 then
MessageDlg('An Error occurred with Mail!',mtError,[mbOK],0);