InkAnalyzer.FindNodes Method (MatchesCriteriaCallback, Object)

Article
12/12/2007

Returns a ContextNodeCollection that contains all of the ContextNode objects that match the specified criteria.

Namespace: System.Windows.Ink
Assembly: IAWinFX (in iawinfx.dll)

Syntax

'Declaration
Public Function FindNodes ( _
    criteria As MatchesCriteriaCallback, _
    data As Object _
) As ContextNodeCollection
'Usage
Dim instance As InkAnalyzer
Dim criteria As MatchesCriteriaCallback
Dim data As Object
Dim returnValue As ContextNodeCollection

returnValue = instance.FindNodes(criteria, data)

public ContextNodeCollection FindNodes (
    MatchesCriteriaCallback criteria,
    Object data
)

public:
ContextNodeCollection^ FindNodes (
    MatchesCriteriaCallback^ criteria, 
    Object^ data
)

public ContextNodeCollection FindNodes (
    MatchesCriteriaCallback criteria, 
    Object data
)

public function FindNodes (
    criteria : MatchesCriteriaCallback, 
    data : Object
) : ContextNodeCollection

Not applicable.

Parameters

criteria
A delegate function that determines if a ContextNode object meets or fails its specified criteria.

data
Optional extra data that may be passed into the delegate function. This method passes this data to the delegate with each call and does not modify or examine it.

Return Value

A ContextNodeCollection containing all of the ContextNode objects that match the specified criteria.

Example

The following example finds the collection of context nodes in the InkAnalyzer, theInkAnalyzer, that satisfy the criteria specified in the LineIsLowerThan delegate. The 32-bit signed integer, yValue, is passed to the LineIsLowerThan delegate.

Dim lineIsLowerThanCallback As New MatchesCriteriaCallback(AddressOf LineIsLowerThan)
Dim nodesBelowYValue As ContextNodeCollection = theInkAnalyzer.FindNodes(lineIsLowerThanCallback, yValue)

MatchesCriteriaCallback
    lineIsLowerThanCallback = new MatchesCriteriaCallback(LineIsLowerThan);
ContextNodeCollection nodesBelowYValue =
    theInkAnalyzer.FindNodes(lineIsLowerThanCallback, yValue);

The following example defines the LineIsLowerThan method, which returns true if the ContextNode is a LineNode and if the bottom of the bounding box is lower than an integer that is passed in. (Note that coordinates are expressed in relation to the top left corner of the window. The more you move down, the higher the y-coordinate is.) Therefore, the nodesBelowYValue collection contains all lines with strokes below the value, yValue.

Public Function LineIsLowerThan(ByVal node As ContextNode, ByVal data As Object) As Boolean 
    ' Return false if not a line
    If Not TypeOf node Is LineNode Then
        Return False
    End If 
    ' Check if bottom is lower than yValue passed in
    Dim yValue As Double = System.Convert.ToDouble(data)
    Return node.Location.GetBounds().Bottom > yValue

End Function 'LineIsLowerThan

public bool LineIsLowerThan(ContextNode node, object data)
{
    // Return false if not a line
    if (!(node is LineNode))
        return false;

    // Check if bottom is lower than yValue passed in
    double yValue = (double)data;
    return (node.Location.GetBounds().Bottom > yValue);
}

Platforms

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

Version Information

.NET Framework

Supported in: 3.0

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