为什么我用ZLIB解压缩的文件无法打开呢？

Question

为什么我用ZLIB解压缩的文件无法打开呢？我的代码如下：
unit Unit1;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs,zlib, StdCtrls;type
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    OpenDialog1: TOpenDialog;
    SaveDialog1: TSaveDialog;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;var
  Form1: TForm1;
  count: integer;implementation{$R *.dfm}procedure TForm1.Button1Click(Sender: TObject);
var
  SourceStream:Tfilestream;
  DestStream:TfileStream;
  CompressStream:TCompressionStream;
begin
  if opendialog1.Execute then
    begin
     SourceStream:=TFilestream.Create(opendialog1.FileName,fmopenread);
     DestStream:=TFileStream.Create (opendialog1.FileName+'.cse',fmCreate);
     CompressStream:=TCompressionStream.Create(clmax,DestStream);
     compressStream.CopyFrom(SourceStream,SourceStream.Size);
     count:=SourceStream.Size;
    end;
   SourceStream.Free;
   DestStream.Free;
end;procedure TForm1.Button2Click(Sender: TObject);
var
  SourceStream:Tfilestream;
  DestStream:TfileStream;
  CompressStream:TDeCompressionStream;
  buffer:pointer;
  //Buffer: array of Char;begin
  if opendialog1.Execute then
        SourceStream:=TFilestream.Create(opendialog1.FileName,fmopenread);
  if savedialog1.Execute then
     DestStream:=TFileStream.Create (Savedialog1.FileName ,fmCreate);
     CompressStream:=TDeCompressionStream.Create(SourceStream);
     //setlength(buffer,count);
   getmem(buffer,SourceStream);
   CompressStream.Read(buffer^,count+1);
   DestStream.Write(buffer^,count+1);
   freemem(buffer,count+1);
   SourceStream.Free;
   DestStream.Free;
end;end.
不知道错在哪里请高手指点，谢谢！

Answer 1

getmem(buffer,SourceStream);
改成
getmem(buffer,count);