c# - 在 Windows Phone 7 中画线？

Question

我想用路径画一些线。运行程序时它总是显示错误。错误发生在这句话:“myPathSegmentCollection.Add(myLineSegment[i]);”可以构建解决方案。调试时显示“元素已经是另一个元素的子元素”

以下是我的功能:

public void drawline(Point endP)
{
    PathFigenter code hereure myPathFigure = new PathFigure();
    myPathFigure.StartPoint = endP;

    LineSegment [] myLineSegment = new LineSegment[5];
    Point myPoint = new Point();
    LineSegment line = new LineSegment();
    PathSegmentCollection myPathSegmentCollection = new PathSegmentCollection();
    for (int i = 0; i < 5; i++)
    {
        myPoint.X = i + 10.0;
        myPoint.Y = i+1.0;
        line.Point = myPoint;
        myLineSegment[i] = line;
        myPathSegmentCollection.Add(myLineSegment[i]);
    } 

    myPathFigure.Segments = myPathSegmentCollection;

    PathFigureCollection myPathFigureCollection = new PathFigureCollection();
    myPathFigureCollection.Add(myPathFigure);

    PathGeometry myPathGeometry = new PathGeometry();
    myPathGeometry.Figures = myPathFigureCollection;

    myPath.StrokeThickness = 1;
    myPath.Data = myPathGeometry;
}

有没有人可以帮忙？谢谢!

Answer 1

问题是您在循环中重新使用了 LineSegment。这些只能作为单个控件的父级，因此多次尝试添加相同的项目会引发异常。

要修复它，请在循环中创建一个新的 LineSegment:

for (int i = 0; i < 5; i++)
{
    myLineSegment[i] = new LineSegment() {
       Point = new Point(i + 10.0, i + 1.0);
    };
    myPathSegmentCollection.Add(myLineSegment[i]);
}