Delphi + Word 问题

Question

我贴上我的全部的测试程序请高手指点。 
主要问题是程序只能运行一次，我想再次运行就出问题，请问是什么地方的原因。 
unit   Unit1; interface uses 
    Windows,   Messages,   SysUtils,   Variants,   Classes,   Graphics,   Controls,   Forms, 
    Dialogs,   StdCtrls,   Word2000,   OleServer; type 
    TForm1   =   class(TForm) 
        WordApplication1:   TWordApplication; 
        WordDocument1:   TWordDocument; 
        Button1:   TButton; 
        Button2:   TButton; 
        Button3:   TButton; 
        Button4:   TButton; 
        procedure   Button1Click(Sender:   TObject); 
        procedure   FormClose(Sender:   TObject;   var   Action:   TCloseAction); 
        procedure   Button2Click(Sender:   TObject); 
        procedure   Button3Click(Sender:   TObject); 
        procedure   Button4Click(Sender:   TObject); 
        procedure   B_replace(ss1:String;ss2:String); 
        procedure   B_close; 
    private 
        {   Private   declarations   } 
    public 
        {   Public   declarations   } 
    end; var 
    Form1:   TForm1; implementation {$R   *.dfm} procedure   TForm1.B_close; 
var 
    savechanges,   originalformat,   routedocument:   olevariant; 
begin 
    savechanges   :=   "C:\Documents   and   Settings\Administrator\桌面\油品购销合同.doc "; 
    originalformat   :=   unassigned; 
    routedocument   :=   unassigned; 
    try 
        WordDocument1.SaveAs(savechanges); 
        WordDocument1.Close; 
        WordDocument1.Free; 
        WordApplication1.Disconnect; 
        WordApplication1.Quit; 
    except 
        on   e:   exception   do 
        begin 
            showmessage(e.message); 
            WordApplication1.disconnect; 
        end; 
    end; 
end; procedure   TForm1.B_replace(ss1:String;ss2:String); 
var           
    findtext,matchcase,matchwholeword,matchwildcards,matchsoundslike, 
    matchallwordforms,s_forward,wrap,format,replacewith,replace,s1,s2,s3,s4:olevariant; 
begin 
    findtext:=ss1; 
    matchcase:=false; 
    matchwholeword:=true; 
    matchwildcards:=false; 
    matchsoundslike:=false; 
    matchallwordforms:=false; 
    s_forward:=false; 
    wrap:=wdfindcontinue; 
    format:=false; 
    replacewith:=ss2; 
    replace:=true;   s1:=false;   s2:=false;s3:=false;s4:=false; 
    WordDocument1.Range.Find.Execute(findtext,matchcase,matchwholeword,matchwildcards,matchsoundslike, 
        matchallwordforms,s_forward,wrap,format,replacewith,replace,s1,s2,s3,s4); end; procedure   TForm1.Button1Click(Sender:   TObject); 
begin 
    try 
        WordApplication1.Connect; 
    except 
        Showmessage( "Word没有正确安装！您不能使用该功能！ "); 
        exit; 
    end; 
    WordApplication1.Visible:=true; 
    WordApplication1.Caption:= "油品购销合同 "; 
end; procedure   TForm1.Button2Click(Sender:   TObject); 
begin 
    Button3Click(Sender); 
    WordApplication1.Visible:=true; 
    B_replace( "name ", "上海良惠检测仪器厂 "); 
    B_replace( "dz ", " "); 
    B_replace( "dh ", " "); 
    B_replace( "yb ", " "); 
    B_replace( "wzmc ", "特种溶剂油 "); 
    B_replace( "wzsl ", "40吨 "); 
    B_replace( "jsjg ", "5000元/吨 "); 
    B_replace( "zje ", "20万元 "); 
    B_replace( "dx ", "贰拾零万零仟零佰零拾零元零角零分 "); 
    B_replace( "GXXXX-XX-XX-XXXX ", "XS2007080001 "); 
    B_close; 
end; procedure   TForm1.Button3Click(Sender:   TObject); 
var           
    itemindex:olevariant; 
    filename,confirmconversions,readonly,addtorecentfiles,passworddocument,passwordtemplate, 
    revert,writepassworddocument,writepasswordtemplate,format,t1,t2:olevariant; 
begin 
    filename:= "E:\操作Word文档\myword\油品购销合同.doc "; 
    confirmconversions:=false;readonly:=false; 
    addtorecentfiles:=false; 
    passworddocument:= " "; 
    passwordtemplate:= " ";revert:=true;t1:=false;   t2:=false; 
    writepassworddocument:= " "; 
    writepasswordtemplate:= " "; 
    format:=wdopenformatdocument; 
        
    WordApplication1.documents.open(filename,confirmconversions, 
        readonly,addtorecentfiles,passworddocument,passwordtemplate, 
        revert,writepassworddocument,writepasswordtemplate,format,t1,t2); 
    itemindex:=1; 
    WordDocument1.connectto(WordApplication1.documents.item(itemindex)); 
    WordApplication1.options.checkspellingasyoutype:=false; 
    WordApplication1.options.checkgrammarasyoutype:=false; 
end; 
procedure   TForm1.Button4Click(Sender:   TObject); 
begin 
    //WordApplication1.Visible:=false; 
close; 
end; end.