我正在尝试更新RichEdit,以便它检测URL并允许单击它以在浏览器中打开.检测URL很简单,我只使用
http://www.scalabium.com/faq/dct0146.htm中的以下代码
mask := SendMessage(MNote.Handle,EM_GETEVENTMASK,0); SendMessage(MNote.Handle,EM_SETEVENTMASK,mask or ENM_LINK); SendMessage(MNote.Handle,EM_AUTOURLDETECT,Integer(True),0);
但第二部分对我不起作用.他们提供以下代码来捕获EN_LINK消息并对其进行处理：
type
TForm1 = class(TForm)
protected
procedure WndProc(var Message: TMessage); override;
end;
...
procedure TForm1.WndProc(var Message: TMessage);
var
p: TENLink;
strURL: string;
begin
if (Message.Msg = WM_NOTIFY) then
begin
if (PNMHDR(Message.LParam).code = EN_LINK) then
begin
p := TENLink(Pointer(TWMNotify(Message).NMHdr)^);
if (p.msg = WM_LBUTTONDOWN) then
begin
SendMessage(RichEdit1.Handle,EM_EXSETSEL,LongInt(@(p.chrg)));
strURL := RichEdit1.SelText;
ShellExecute(Handle,'open',PChar(strURL),SW_SHOWNORMAL);
end
end
end;
inherited;
end;
当我运行程序时,检测到URL,但点击它不会做任何事情.使用调试我发现当我点击URL时,Message.Msg = WM_NOTIFY不成立.然后我试图覆盖TRichEdit的WndProc,但结果是一样的.有什么建议么？
解决方法
对RichEdit的WindowProc属性进行子类化并查找CN_NOTIFY消息,例如：
type
TForm1 = class(TForm)
RichEdit1: TRichEdit;
procedure FormCreate(Sender: TObject);
private
PrevRichEditWndProc: TWndMethod;
procedure RichEditWndProc(var Message: TMessage);
procedure SetRichEditMasks;
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
PrevRichEditWndProc := RichEdit1.WindowProc;
RichEdit1.WindowProc := RichEditWndProc;
SetRichEditMasks;
end;
procedure TForm1.SetRichEditMasks;
var
mask: Longint;
begin
mask := SendMessage(RichEdit1.Handle,0);
SendMessage(RichEdit1.Handle,mask or ENM_LINK);
SendMessage(RichEdit1.Handle,1,0);
end;
procedure TForm1.RichEditWndProc(var Message: TMessage);
begin
PrevRichEditWndProc(Message);
case Message.Msg of
CN_NOTIFY:
begin
if (TWMNotify(Message).NMHdr^.code = EN_LINK) then
begin
with PENLink(Message.LParam)^ do
begin
if (msg = WM_LBUTTONDOWN) then
begin
SendMessage(RichEdit1.Handle,LongInt(@chrg));
ShellExecute(Handle,PChar(RichEdit1.SelText),SW_SHOWNORMAL);
end;
end;
end;
end;
CM_RECREATEWND:
begin
SetRichEditMasks;
end;
end;
end;