对象访问出错
unit sql;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls,
xmldom, XMLIntf, msxmldom, XMLDoc, ComCtrls,xmlset
;
type
Tsqlfrm = class(TForm)
AddXM: TButton;
Button2: TButton;
Edit1: TEdit;
Edit2: TEdit;
XMLDoc1: TXMLDocument;
procedure Button2Click(Sender: TObject);
procedure AddXMClick(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
pstr=^string;
var
sqlfrm: Tsqlfrm;
root:IXMLNode;
parent_node:IXMLNode;
child_node:IXMLNode;
a:Txmlset; //另一单元定义的一个类
implementation
//uses xmlset;
{$R *.dfm}
procedure Tsqlfrm.Button2Click(Sender: TObject);
begin
a:=Txmlset.Create(xmldoc1,'bb.xml');
a.WriteParam('style',Edit2.Text);
Edit1.Text:=a.ReadParam('style'); //正常
a.SaveSet;
a.Free;
end;
procedure Tsqlfrm.AddXMClick(Sender: TObject);
begin
Edit1.Text:=a.ReadParam('style'); //不能读取数据
end;
执行顺序是先执行Button2Click，再执行AddXMClick
问题点数：20、回复次数：3Top
1 楼Tensionli（）回复于 2006-03-29 12:36:53 得分 20
a已经free掉了，还能使用吗？Top
2 楼blns（骑士007）回复于 2006-03-29 12:46:49 得分 0
失误失误，哈哈，感谢Top
3 楼zhangl_cn（和尚-修行）回复于 2006-03-29 18:06:36 得分 0
呵呵,只能顶一下了,顺便接点分Top
