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Holds Syncfusion FAQs and specific data

I’m trying to make the background of my linklabel transparent so a picturebox will show through it. However, if I set the link label’s BackColor property to Transparent the label still has a white background. Why

Controls with a ‘Transparent’ color actually render their parent’s background, so you’re seeing the White background of the Form, not the PictureBox. Three easy ways to deal with this: Use a Panel with it’s ‘BackgroundImage’ property set instead of a PictureBox, and parent the LinkLabels to the panel (PictureBoxes generally don’t have children) Set the BackgroundImage of the Form to the image (basically the same as 1 above, but avoids the extra control) In code, set the Parent of the LinkLabel to be the PictureBox. You’ll need to update the LinkLabel’s position to match the new origin of the parent if the PictureBox isn’t at (0,0) (Shawn Burke on microsoft.public.dotnet.framework.windowsforms newsgroup)

How can I catch the BeforeNavigate2 event?

This is a known bug. See http://support.microsoft.com/default.aspx?scid=KB;EN-US;Q311298&ID=KB;EN-US; If you are using the second solution from our FAQ ‘How can I host a WebBrowser control in a Windows Form’ you will not have this problem but if you use the automatically generated wrapper classes see the following solution: John Cullen posted the following answer in the microsoft.public.dotnet.framework.interop newsgroup. The problem of the BeforeNavigate2 event not firing in C# applications has been floating around various groups for several months. Microsoft have not yet fixed the problem, although it is documented in the knowledge base. Until they do provide a fix, I suggest the following workaround to the problem which uses the fact the the old Webbrowser_V1 BeforeNavigate event *can* be caught. Note, use of this interface is deprecated, however since there doesn’t appear to be any chance of a fix any time soon… … // define the webbrowser object private AxSHDocVw.AxWebBrowser axDocument; // define an IE3 compatible webbrowser object. private SHDocVw.WebBrowser_V1 axDocumentV1; public Form1() { //… object o = null; axDocument.Navigate(‘about:blank’, ref o, ref o, ref o, ref o); object oOcx = axDocument.GetOcx(); try { axDocumentV1 = oOcx as WebBrowser_V1; axDocumentV1.BeforeNavigate += new SHDocVw.DWebBrowserEvents_BeforeNavigateEventHandler(this.axDocumentV1_BeforeNavigate); } catch (Exception ex) { // ignore errors. If it doesn’t work, there’s not a lot to do! Console.WriteLine(‘Add BeforeNavigate event handler failed with{0}.’, ex.Message); } //… } private void axDocumentV1_BeforeNavigate(string URL, int Flags, string TargetFrameName, ref object PostData, string Headers, ref bool Processed) { Console.WriteLine(‘BeforeNavigateURL= {0}’, URL); //false= allow navigate to continue. //true= cancel navigation. Processed=false; }

How can I enable editing for the WebBrowser?

You can set the content editable by getting a reference to a IHTMLElement3 element and initializing the contentEditable property with ‘true’. private void EnableEditing() { IHTMLDocument3 doc = (IHTMLDocument3) browser.GetDocument(); if (doc != null) { IHTMLElement3 el = (IHTMLElement3) doc.GetBody(); el.contentEditable = ‘true’; } } If you want to read out contents of a specific element use an id in the html source: <span id=’EditText’>EditableText</span> From CSharp you can reference this text with IHTMLElement3 el = (IHTMLElement3) doc.getElementById(‘EditText’); MessageBox.Show(el.GetInnerText()); MessageBox.Show(el.GetInnerHTML()); You can use IHTMLDocument3 and IHTMLElement3 interface definitions from the imported type library dll C:\Program Files\Microsoft.NET\Primary Interop Assemblies\Microsoft.mshtml.dll [ Guid(@’3050F485-98B5-11CF-BB82-00AA00BDCE0B’), TypeLibType(TypeLibTypeFlags.FDispatchable|TypeLibTypeFlags.FDual) ] public interface IHTMLDocument3 : IHTMLDocument2 { [DispId(1072 /*0x0430*/)] void releaseCapture(); [DispId(1073 /*0x0431*/)] void recalc(bool fForce); [DispId(1074 /*0x0432*/)] [return: MarshalAs(UnmanagedType.Interface)] object createTextNode(string text); [DispId(1075 /*0x0433*/)] IHTMLElement documentElement { [return: MarshalAs(UnmanagedType.Interface)] get; } [DispId(1077 /*0x0435*/)] string uniqueID { [return: MarshalAs(UnmanagedType.BStr)] get; } [DispId(-2147417605 /*0x800101FB*/)] bool attachEvent(string _event, object pdisp); [DispId(-2147417604 /*0x800101FC*/)] void detachEvent(string _event, object pdisp); [DispId(-2147412050 /*0x800117AE*/)] object onrowsdelete { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412049 /*0x800117AF*/)] object onrowsinserted { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412048 /*0x800117B0*/)] object oncellchange { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412072 /*0x80011798*/)] object ondatasetchanged { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412071 /*0x80011799*/)] object ondataavailable { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412070 /*0x8001179A*/)] object ondatasetcomplete { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412065 /*0x8001179F*/)] object onpropertychange { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412995 /*0x800113FD*/)] string dir { set; [return: MarshalAs(UnmanagedType.BStr)] get; } [DispId(-2147412047 /*0x800117B1*/)] object oncontextmenu { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412044 /*0x800117B4*/)] object onstop { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(1076 /*0x0434*/)] [return: MarshalAs(UnmanagedType.Interface)] IHTMLDocument2 createDocumentFragment(); [DispId(1078 /*0x0436*/)] IHTMLDocument2 parentDocument { [return: MarshalAs(UnmanagedType.Interface)] get; } [DispId(1079 /*0x0437*/)] bool enableDownload { set; get; } [DispId(1080 /*0x0438*/)] string baseUrl { set; [return: MarshalAs(UnmanagedType.BStr)] get; } [DispId(-2147417063 /*0x80010419*/)] object childNodes { [return: MarshalAs(UnmanagedType.IDispatch)] get; } [DispId(1082 /*0x043A*/)] bool inheritStyleSheets { set; get; } [DispId(-2147412043 /*0x800117B5*/)] object onbeforeeditfocus { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(1086 /*0x043E*/)] [return: MarshalAs(UnmanagedType.Interface)] object getElementsByName(string v); [DispId(1088 /*0x0440*/)] [return: MarshalAs(UnmanagedType.Interface)] IHTMLElement getElementById(string v); [DispId(1087 /*0x043F*/)] [return: MarshalAs(UnmanagedType.Interface)] object getElementsByTagName(string v); } [ InterfaceType(ComInterfaceType.InterfaceIsDual), ComVisible(true), Guid(@’332C4425-26CB-11D0-B483-00C04FD90119′) ] public interface IHTMLDocument2 { [return: MarshalAs(UnmanagedType.Interface)] object GetScript(); [return: MarshalAs(UnmanagedType.Interface)] object GetAll(); [return: MarshalAs(UnmanagedType.Interface)] IHTMLElement GetBody(); [return: MarshalAs(UnmanagedType.Interface)] object GetActiveElement(); [return: MarshalAs(UnmanagedType.Interface)] object GetImages(); [return: MarshalAs(UnmanagedType.Interface)] object GetApplets(); [return: MarshalAs(UnmanagedType.Interface)] object GetLinks(); [return: MarshalAs(UnmanagedType.Interface)] object GetForms(); [return: MarshalAs(UnmanagedType.Interface)] object GetAnchors(); void SetTitle(string p); [return: MarshalAs(UnmanagedType.BStr)] string GetTitle(); [return: MarshalAs(UnmanagedType.Interface)] object GetScripts(); void SetDesignMode(string p); [return: MarshalAs(UnmanagedType.BStr)] string GetDesignMode(); [return: MarshalAs(UnmanagedType.Interface)] object GetSelection(); [return: MarshalAs(UnmanagedType.BStr)] string GetReadyState(); [return: MarshalAs(UnmanagedType.Interface)] object GetFrames(); [return: MarshalAs(UnmanagedType.Interface)] object GetEmbeds(); [return: MarshalAs(UnmanagedType.Interface)] object GetPlugins(); void SetAlinkColor(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetAlinkColor(); void SetBgColor(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetBgColor(); void SetFgColor(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetFgColor(); void SetLinkColor(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetLinkColor(); void SetVlinkColor(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetVlinkColor(); [return: MarshalAs(UnmanagedType.BStr)] string GetReferrer(); [return: MarshalAs(UnmanagedType.Interface)] object GetLocation(); [return: MarshalAs(UnmanagedType.BStr)] string GetLastModified(); void SetURL(string p); [return: MarshalAs(UnmanagedType.BStr)] string GetURL(); void SetDomain(string p); [return: MarshalAs(UnmanagedType.BStr)] string GetDomain(); void SetCookie(string p); [return: MarshalAs(UnmanagedType.BStr)] string GetCookie(); void SetExpando(bool p); [return: MarshalAs(UnmanagedType.Bool)] bool GetExpando(); void SetCharset(string p); [return: MarshalAs(UnmanagedType.BStr)] string GetCharset(); void SetDefaultCharset(string p); [return: MarshalAs(UnmanagedType.BStr)] string GetDefaultCharset(); [return: MarshalAs(UnmanagedType.BStr)] string GetMimeType(); [return: MarshalAs(UnmanagedType.BStr)] string GetFileSize(); [return: MarshalAs(UnmanagedType.BStr)] string GetFileCreatedDate(); [return: MarshalAs(UnmanagedType.BStr)] string GetFileModifiedDate(); [return: MarshalAs(UnmanagedType.BStr)] string GetFileUpdatedDate(); [return: MarshalAs(UnmanagedType.BStr)] string GetSecurity(); [return: MarshalAs(UnmanagedType.BStr)] string GetProtocol(); [return: MarshalAs(UnmanagedType.BStr)] string GetNameProp(); void DummyWrite(int psarray); void DummyWriteln(int psarray); [return: MarshalAs(UnmanagedType.Interface)] object Open(string URL, object name, object features, object replace); void Close(); void Clear(); [return: MarshalAs(UnmanagedType.Bool)] bool QueryCommandSupported(string cmdID); [return: MarshalAs(UnmanagedType.Bool)] bool QueryCommandEnabled(string cmdID); [return: MarshalAs(UnmanagedType.Bool)] bool QueryCommandState(string cmdID); [return: MarshalAs(UnmanagedType.Bool)] bool QueryCommandIndeterm(string cmdID); [return: MarshalAs(UnmanagedType.BStr)] string QueryCommandText(string cmdID); [return: MarshalAs(UnmanagedType.Struct)] object QueryCommandValue(string cmdID); [return: MarshalAs(UnmanagedType.Bool)] bool ExecCommand(string cmdID, bool showUI, object value); [return: MarshalAs(UnmanagedType.Bool)] bool ExecCommandShowHelp(string cmdID); [return: MarshalAs(UnmanagedType.Interface)] object CreateElement(string eTag); void SetOnhelp(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnhelp(); void SetOnclick(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnclick(); void SetOndblclick(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOndblclick(); void SetOnkeyup(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnkeyup(); void SetOnkeydown(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnkeydown(); void SetOnkeypress(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnkeypress(); void SetOnmouseup(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnmouseup(); void SetOnmousedown(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnmousedown(); void SetOnmousemove(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnmousemove(); void SetOnmouseout(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnmouseout(); void SetOnmouseover(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnmouseover(); void SetOnreadystatechange(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnreadystatechange(); void SetOnafterupdate(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnafterupdate(); void SetOnrowexit(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnrowexit(); void SetOnrowenter(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnrowenter(); void SetOndragstart(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOndragstart(); void SetOnselectstart(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnselectstart(); [return: MarshalAs(UnmanagedType.Interface)] object ElementFromPoint(int x, int y); [return: MarshalAs(UnmanagedType.Interface)] object GetParentWindow(); [return: MarshalAs(UnmanagedType.Interface)] object GetStyleSheets(); void SetOnbeforeupdate(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnbeforeupdate(); void SetOnerrorupdate(object p); [return: MarshalAs(UnmanagedType.Struct)] object GetOnerrorupdate(); [return: MarshalAs(UnmanagedType.BStr)] string toString(); [return: MarshalAs(UnmanagedType.Interface)] object CreateStyleSheet(string bstrHref, int lIndex); } [ Guid(@’3050F434-98B5-11CF-BB82-00AA00BDCE0B’), TypeLibType(TypeLibTypeFlags.FDispatchable|TypeLibTypeFlags.FDual) ] public interface IHTMLElement2 : IHTMLElement { // Methods [DispId(-2147417073 /*0x8001040F*/)] string scopeName { [return: MarshalAs(UnmanagedType.BStr)] get; } [DispId(-2147417072 /*0x80010410*/)] void setCapture(bool containerCapture); [DispId(-2147417071 /*0x80010411*/)] void releaseCapture(); [DispId(-2147412066 /*0x8001179E*/)] object onlosecapture { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147417070 /*0x80010412*/)] [return: MarshalAs(UnmanagedType.BStr)] string componentFromPoint(int x, int y); [DispId(-2147417069 /*0x80010413*/)] void doScroll(object component); [DispId(-2147412081 /*0x8001178F*/)] object onscroll { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412063 /*0x800117A1*/)] object ondrag { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412062 /*0x800117A2*/)] object ondragend { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412061 /*0x800117A3*/)] object ondragenter { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412060 /*0x800117A4*/)] object ondragover { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412059 /*0x800117A5*/)] object ondragleave { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412058 /*0x800117A6*/)] object ondrop { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412054 /*0x800117AA*/)] object onbeforecut { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412057 /*0x800117A7*/)] object oncut { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412053 /*0x800117AB*/)] object onbeforecopy { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412056 /*0x800117A8*/)] object oncopy { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412052 /*0x800117AC*/)] object onbeforepaste { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147412055 /*0x800117A9*/)] object onpaste { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147417105 /*0x800103EF*/)] object currentStyle { [return: MarshalAs(UnmanagedType.Interface)] get; } [DispId(-2147412065 /*0x8001179F*/)] object onpropertychange { set; [return: MarshalAs(UnmanagedType.Struct)] get; } [DispId(-2147417068 /*0x80010414*/)] [return: MarshalAs(UnmanagedType.Interface)] object getClientRects(); [DispId(-2147417067 /*0x80010415*/)] [return: MarshalAs(UnmanagedType.Interface)] object getBoundingClientRect(); [DispId(-2147417608 /*0x800101F8*/)] void setExpression(string propname, string expression, string language); [DispId(-2147417607 /*0x800101F9*/)] [return: