GraphicsPathIterator.NextPathType(Byte, Int32, Int32) 方法
定义
重要
一些信息与预发行产品相关,相应产品在发行之前可能会进行重大修改。 对于此处提供的信息,Microsoft 不作任何明示或暗示的担保。
获取具有相同类型的下一组数据点的起始索引和结束索引。
public:
int NextPathType([Runtime::InteropServices::Out] System::Byte % pathType, [Runtime::InteropServices::Out] int % startIndex, [Runtime::InteropServices::Out] int % endIndex);
public int NextPathType (out byte pathType, out int startIndex, out int endIndex);
member this.NextPathType : byte * int * int -> int
Public Function NextPathType (ByRef pathType As Byte, ByRef startIndex As Integer, ByRef endIndex As Integer) As Integer
参数
- pathType
- Byte
[out]接收组中所有点共享的点类型。 可以从 PathPointType 枚举中检索可能的类型。
- startIndex
- Int32
[out]接收点组的起始索引。
- endIndex
- Int32
[out]接收点组的结束索引。
返回
此方法返回组中的数据点数。 如果路径中没有更多组,则此方法返回 0。
示例
以下示例旨在与 Windows 窗体一起使用,它需要 PaintEventArgse
OnPaint 事件对象。 该代码执行以下操作:
创建 GraphicsPath 对象。
添加三行、一个矩形和椭圆。
列出所有指向屏幕左侧的点的值。
创建 GraphicsPathIterator 并将其倒退。
在
for
循环中,使用 NextPathType 和 NextPathType 方法循环访问点。使用迭代调用返回的值列出子路径编号、其中点数以及屏幕右侧的路径点的类型。
显示指向屏幕的点总数的值。
请注意,ListPathPoints
是一个帮助程序函数,用于将显示代码中的大多数(并非全部)与图形路径代码分开。
public:
void NextPathTypeExample( PaintEventArgs^ e )
{
// Create the GraphicsPath.
GraphicsPath^ myPath = gcnew GraphicsPath;
array<Point>^ myPoints = {Point(20,20),Point(120,120),Point(20,120),Point(20,20)};
Rectangle myRect = Rectangle(120,120,100,100);
// Add 3 lines, a rectangle, and an ellipse.
myPath->AddLines( myPoints );
myPath->AddRectangle( myRect );
myPath->AddEllipse( 220, 220, 100, 100 );
// List all of the path points to the screen.
ListPathPoints( e, myPath, nullptr, 20, 1 );
// Create a GraphicsPathIterator.
GraphicsPathIterator^ myPathIterator = gcnew GraphicsPathIterator( myPath );
// Rewind the Iterator.
myPathIterator->Rewind();
// Iterate the subpaths and types, and list the results to
// the screen.
int i;
int j = 20;
int mySubPaths;
int subPathStartIndex;
int subPathEndIndex;
Boolean IsClosed;
Byte subPathPointType;
int pointTypeStartIndex;
int pointTypeEndIndex;
int numPointsFound;
System::Drawing::Font^ myFont = gcnew System::Drawing::Font( "Arial",8 );
SolidBrush^ myBrush = gcnew SolidBrush( Color::Black );
j = 20;
for ( i = 0; i < 3; i++ )
{
mySubPaths = myPathIterator->NextSubpath( subPathStartIndex, subPathEndIndex, IsClosed );
numPointsFound = myPathIterator->NextPathType( subPathPointType, pointTypeStartIndex, pointTypeEndIndex );
e->Graphics->DrawString( String::Format( "SubPath: {0} Points Found: {1} Type of Points: {2}", i,
numPointsFound, subPathPointType ), myFont, myBrush, 200.0f, (float)j );
j += 20;
}
// List the total number of path points to the screen.
ListPathPoints( e, myPath, myPathIterator, 200, 2 );
}
//-------------------------------------------------------
//This function is a helper function used by
// NextPathTypeExample.
//-------------------------------------------------------
void ListPathPoints( PaintEventArgs^ e, GraphicsPath^ myPath, GraphicsPathIterator^ myPathIterator, int xOffset, int listType )
{
// Get the total number of points for the path,
// and the arrays of the points and types.
int myPathPointCount = myPath->PointCount;
array<PointF>^myPathPoints = myPath->PathPoints;
array<Byte>^myPathTypes = myPath->PathTypes;
// Set up variables for drawing the points to the screen.
int i;
float j = 20;
System::Drawing::Font^ myFont = gcnew System::Drawing::Font( "Arial",8 );
SolidBrush^ myBrush = gcnew SolidBrush( Color::Black );
if ( listType == 1 )
{
// Draw the set of path points and types to the screen.
for ( i = 0; i < myPathPointCount; i++ )
{
e->Graphics->DrawString( myPathPoints[ i ].X + ", " + myPathPoints[ i ].Y + ", " + myPathTypes[ i ],
myFont, myBrush, (float)xOffset, (float)j );
j += 20;
}
}
else
if ( listType == 2 )
{
// Draw the total number of points to the screen.
int myPathTotalPoints = myPathIterator->Count;
e->Graphics->DrawString( String::Format( "Total Points = {0}", myPathTotalPoints ), myFont, myBrush, (float)xOffset, 100.0f );
}
else
{
e->Graphics->DrawString( "Wrong or no list type argument.", myFont, myBrush, (float)xOffset, 200.0f );
}
}
public void NextPathTypeExample(PaintEventArgs e)
{
// Create the GraphicsPath.
GraphicsPath myPath = new GraphicsPath();
Point[] myPoints = {new Point(20, 20), new Point(120, 120),
new Point(20, 120),new Point(20, 20) };
Rectangle myRect = new Rectangle(120, 120, 100, 100);
// Add 3 lines, a rectangle, and an ellipse.
myPath.AddLines(myPoints);
myPath.AddRectangle(myRect);
myPath.AddEllipse(220, 220, 100, 100);
// List all of the path points to the screen.
ListPathPoints(e, myPath, null, 20, 1);
// Create a GraphicsPathIterator.
GraphicsPathIterator myPathIterator = new
GraphicsPathIterator(myPath);
// Rewind the Iterator.
myPathIterator.Rewind();
// Iterate the subpaths and types, and list the results to
// the screen.
int i, j = 20;
int mySubPaths, subPathStartIndex, subPathEndIndex;
Boolean IsClosed;
byte subPathPointType;
int pointTypeStartIndex, pointTypeEndIndex, numPointsFound;
Font myFont = new Font("Arial", 8);
SolidBrush myBrush = new SolidBrush(Color.Black);
j = 20;
for(i = 0;i < 3; i++)
{
mySubPaths = myPathIterator.NextSubpath(
out subPathStartIndex,
out subPathEndIndex,
out IsClosed);
numPointsFound = myPathIterator.NextPathType(
out subPathPointType,
out pointTypeStartIndex,
out pointTypeEndIndex);
e.Graphics.DrawString(
"SubPath: " + i +
" Points Found: " + numPointsFound.ToString() +
" Type of Points: " + subPathPointType.ToString(),
myFont,
myBrush,
200,
j);
j+=20;
}
// List the total number of path points to the screen.
ListPathPoints(e, myPath, myPathIterator, 200, 2);
}
//-------------------------------------------------------
//This function is a helper function used by
// NextPathTypeExample.
//-------------------------------------------------------
public void ListPathPoints(
PaintEventArgs e,
GraphicsPath myPath,
GraphicsPathIterator myPathIterator,
int xOffset,
int listType)
{
// Get the total number of points for the path,
// and the arrays of the points and types.
int myPathPointCount = myPath.PointCount;
PointF[] myPathPoints = myPath.PathPoints;
byte[] myPathTypes = myPath.PathTypes;
// Set up variables for drawing the points to the screen.
int i;
float j = 20;
Font myFont = new Font("Arial", 8);
SolidBrush myBrush = new SolidBrush(Color.Black);
if (listType == 1)
// List all the path points to the screen.
{
// Draw the set of path points and types to the screen.
for(i=0; i<myPathPointCount; i++)
{
e.Graphics.DrawString(myPathPoints[i].X.ToString()+
", " + myPathPoints[i].Y.ToString() + ", " +
myPathTypes[i].ToString(),
myFont,
myBrush,
xOffset,
j);
j+=20;
}
}
else if (listType == 2)
// Display the total number of path points.
{
// Draw the total number of points to the screen.
int myPathTotalPoints = myPathIterator.Count;
e.Graphics.DrawString("Total Points = " +
myPathTotalPoints.ToString(),
myFont,
myBrush,
xOffset,
100);
}
else
{
e.Graphics.DrawString("Wrong or no list type argument.",
myFont, myBrush, xOffset, 200);
}
}
Public Sub NextPathTypeExample(ByVal e As PaintEventArgs)
' Create the GraphicsPath.
Dim myPath As New GraphicsPath
Dim myPoints As Point() = {New Point(20, 20), _
New Point(120, 120), New Point(20, 120), New Point(20, 20)}
Dim myRect As New Rectangle(120, 120, 100, 100)
' Add 3 lines, a rectangle, and an ellipse.
myPath.AddLines(myPoints)
myPath.AddRectangle(myRect)
myPath.AddEllipse(220, 220, 100, 100)
' List all of the path points to the screen.
ListPathPointsHelper(e, myPath, Nothing, 20, 1)
' Create a GraphicsPathIterator.
Dim myPathIterator As New GraphicsPathIterator(myPath)
' Rewind the Iterator.
myPathIterator.Rewind()
' Iterate the subpaths and types, and list the results
' to the screen.
Dim j As Integer = 20
Dim i As Integer
Dim mySubPaths, subPathStartIndex, subPathEndIndex As Integer
Dim IsClosed As [Boolean]
Dim subPathPointType As Byte
Dim pointTypeStartIndex, pointTypeEndIndex, _
numPointsFound As Integer
Dim myFont As New Font("Arial", 8)
Dim myBrush As New SolidBrush(Color.Black)
j = 20
For i = 0 To 2
mySubPaths = myPathIterator.NextSubpath(subPathStartIndex, _
subPathEndIndex, IsClosed)
numPointsFound = myPathIterator.NextPathType(subPathPointType, _
pointTypeStartIndex, pointTypeEndIndex)
e.Graphics.DrawString("SubPath: " & i & " Points Found: " & _
numPointsFound.ToString() & " Type of Points: " & _
subPathPointType.ToString(), myFont, myBrush, 200, j)
j += 20
Next i
' List the total number of path points to the screen.
ListPathPointsHelper(e, myPath, myPathIterator, 200, 2)
End Sub
' This is a helper function used by NextPathTypeExample.
Public Sub ListPathPointsHelper(ByVal e As PaintEventArgs, _
ByVal myPath As GraphicsPath, ByVal myPathIterator As GraphicsPathIterator, _
ByVal xOffset As Integer, ByVal listType As Integer)
' Get the total number of points for the path,
' and the arrays of the points and types.
Dim myPathPointCount As Integer = myPath.PointCount
Dim myPathPoints As PointF() = myPath.PathPoints
Dim myPathTypes As Byte() = myPath.PathTypes
' Set up variables for drawing the points to the screen.
Dim i As Integer
Dim j As Single = 20
Dim myFont As New Font("Arial", 8)
Dim myBrush As New SolidBrush(Color.Black)
If listType = 1 Then
' List all the path points to the screen.
' Draw the set of path points and types to the screen.
For i = 0 To myPathPointCount - 1
e.Graphics.DrawString(myPathPoints(i).X.ToString() + ", " + _
myPathPoints(i).Y.ToString() + ", " + _
myPathTypes(i).ToString(), myFont, myBrush, xOffset, j)
j += 20
Next i
Else
If listType = 2 Then
' Display the total number of path points.
' Draw the total number of points to the screen.
Dim myPathTotalPoints As Integer = myPathIterator.Count
e.Graphics.DrawString("Total Points = " + _
myPathTotalPoints.ToString(), myFont, myBrush, xOffset, _
100)
Else
e.Graphics.DrawString("Wrong or no list type argument.", _
myFont, myBrush, xOffset, 200)
End If
End If
End Sub