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HtmlElement.Children Property

Definition

Gets an HtmlElementCollection of all children of the current element.

public:
 property System::Windows::Forms::HtmlElementCollection ^ Children { System::Windows::Forms::HtmlElementCollection ^ get(); };
public System.Windows.Forms.HtmlElementCollection Children { get; }
member this.Children : System.Windows.Forms.HtmlElementCollection
Public ReadOnly Property Children As HtmlElementCollection

Property Value

A collection of all HtmlElement objects that have the current element as a parent.

Examples

The following code example examines an arbitrary HTML document and derive a string describing the elements, with indentation and level numbers used to indicate how deeply nested the elements are in the document. It does this by searching the Children collection of all elements recursively, starting with the HTML element at the top of the document. This code example requires that your application has a WebBrowser control named WebBrowser1.

private void PrintDomBegin()
{
    if (webBrowser1.Document != null)
    {
        HtmlElementCollection elemColl = null;
        HtmlDocument doc = webBrowser1.Document;
        if (doc != null)
        {
            elemColl = doc.GetElementsByTagName("HTML");
            String str = PrintDom(elemColl, new System.Text.StringBuilder(), 0);
            webBrowser1.DocumentText = str;
        }
    }
}

private string PrintDom(HtmlElementCollection elemColl, System.Text.StringBuilder returnStr, Int32 depth)
{
    System.Text.StringBuilder str = new System.Text.StringBuilder();

    foreach (HtmlElement elem in elemColl)
    {
        string elemName;

        elemName = elem.GetAttribute("ID");
        if (elemName == null || elemName.Length == 0)
        {
            elemName = elem.GetAttribute("name");
            if (elemName == null || elemName.Length == 0)
            {
                elemName = "<no name>";
            }
        }

        str.Append(' ', depth * 4);
        str.Append(elemName + ": " + elem.TagName + "(Level " + depth + ")");
        returnStr.AppendLine(str.ToString());

        if (elem.CanHaveChildren)
        {
            PrintDom(elem.Children, returnStr, depth + 1);
        }

        str.Remove(0, str.Length);
    }

    return (returnStr.ToString());
}
Private Sub PrintDomBegin()
    If (WebBrowser1.Document IsNot Nothing) Then
        Dim ElemColl As HtmlElementCollection

        Dim Doc As HtmlDocument = WebBrowser1.Document
        If (Not (Doc Is Nothing)) Then
            ElemColl = Doc.GetElementsByTagName("HTML")
            Dim Str As String = PrintDom(ElemColl, New System.Text.StringBuilder(), 0)

            WebBrowser1.DocumentText = Str
        End If
    End If
End Sub

Private Function PrintDom(ByVal ElemColl As HtmlElementCollection, ByRef ReturnStr As System.Text.StringBuilder, ByVal Depth As Integer) As String
    Dim Str As New System.Text.StringBuilder()

    For Each Elem As HtmlElement In ElemColl
        Dim ElemName As String

        ElemName = Elem.GetAttribute("ID")
        If (ElemName Is Nothing Or ElemName.Length = 0) Then
            ElemName = Elem.GetAttribute("name")
            If (ElemName Is Nothing Or ElemName.Length = 0) Then
                ElemName = "<no name>"
            End If
        End If

        Str.Append(CChar(" "), Depth * 4)
        Str.Append(ElemName & ": " & Elem.TagName & "(Level " & Depth & ")")
        ReturnStr.AppendLine(Str.ToString())

        If (Elem.CanHaveChildren) Then
            PrintDom(Elem.Children, ReturnStr, Depth + 1)
        End If

        Str.Remove(0, Str.Length)
    Next

    PrintDom = ReturnStr.ToString()
End Function

Remarks

Many of the elements inside of an HTML file can have other HTML elements underneath them. The Children collection provides a simple mechanism for exploring the tree structure of a document.

Children only exposes elements whose direct parent is the current element. If you have an HtmlElement for a TABLE element, Children will give you all of the TR (row) elements inside of the TABLE. To retrieve the TD (cell) elements contained inside of the TR elements, you will need to use either the Children collection on each individual TR element, or use the All collection on HtmlElement.

Elements in this collection are not guaranteed to be in source order.

If CanHaveChildren is false, Children will always be empty.

Applies to

See also