HtmlElement.InsertAdjacentElement Method (HtmlElementInsertionOrientation, HtmlElement)


Insert a new element into the Document Object Model (DOM).

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public HtmlElement InsertAdjacentElement(
	HtmlElementInsertionOrientation orient,
	HtmlElement newElement


Type: System.Windows.Forms.HtmlElementInsertionOrientation

Where to insert this element in relation to the current element.

Type: System.Windows.Forms.HtmlElement

The new element to insert.

Return Value

Type: System.Windows.Forms.HtmlElement

The HtmlElement that was just inserted. If insertion failed, this will return null.

Do not call this method until after the DocumentCompleted event on the WebBrowser control has occurred. Calling this method before then can result in an exception, as the document will not have finished loading.

Whether a value of HtmlElementInsertionOrientation is valid will depend on the type of the element. For example, AfterBegin is valid if the element is a DIV, but not if it is a SCRIPT or IMG element, neither of which can contain child elements.

The following code example inserts a DIV element into the top of every page that users view outside of the server. The example requires that your form contains a WebBrowser control named WebBrowser1. Your sample must also import the namespace System.Text.RegularExpressions.

public void AddDivMessage()
	Uri currentUri = new Uri(webBrowser1.Url.ToString());
	String hostName = null;

	// Ensure we have a host name, and not just an IP, against which to test.
	if (!(currentUri.HostNameType == UriHostNameType.Dns))
		DnsPermission permit = new DnsPermission(System.Security.Permissions.PermissionState.Unrestricted);

		IPHostEntry hostEntry = System.Net.Dns.GetHostEntry(currentUri.Host);
		hostName = hostEntry.HostName;
	} else {
		hostName = currentUri.Host;

	if (!hostName.Contains(""))
		AddTopPageMessage("You are viewing a web site other than " +
			"Please exercise caution, and ensure your Web surfing complies with all " +
			"corporate regulations as laid out in the company handbook.");

private void AddTopPageMessage(String message)
	if (webBrowser1.Document != null) 
		HtmlDocument doc = webBrowser1.Document;

              // Do not insert the warning again if it already exists. 
              HtmlElementCollection returnedElems = doc.All.GetElementsByName("ADatumWarningDiv");
              if ((returnedElems != null) && (returnedElems.Count > 0)) 

              HtmlElement divElem = doc.CreateElement("DIV");
              divElem.Name = "ADatumWarningDiv";
              divElem.Style = "background-color:black;color:white;font-weight:bold;width:100%;";
              divElem.InnerText = message;

              divElem = doc.Body.InsertAdjacentElement(HtmlElementInsertionOrientation.AfterBegin, divElem);

.NET Framework
Available since 2.0
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