Use of GDI +

First, create a canvas

Method 1:

this. CreateGraphics ();

Method 2:

New= graphics.fromimage (bitmap);
Picbtrackreplay.image = bitmap;//Specifies the control picture

Using also enables automatic resource recycling of the canvas.

Second, create a brush

1. Creating brushes

using New 2 ) ) {    //  draw statement }

2. Custom Dash Spacing

Pen Gridpen = new Pen (color, 1);      Float[] D = new float[2];      D[0] = 3;      D[1] = 3;      Gridpen. DashPattern = D;      Gridpen. DashStyle = DashStyle.Custom;

3. Custom Arrow Format

New Adjustablearrowcap (44truenew2= LineCap;

Third, drawing

list<pointf> changedpointslist=New list<pointf>();
Draw the line G. DrawLines (RedPen, Changedpointslist.toarray ());
G.drawline (RedPen, New PointF, New PointF (3,4));
Draw a rectangle
G.drawrectangle (Redpen,new PointF, 1, 1);
Drawing polygons
G.drawpolygon (Redpen,changedpointslist.toarry ());
Draw text
g.DrawString ("string", New Font ("Arial", 9), Brushes.black, new PointF);
Fill Color
G.fillpolygon (Brushes.black,changedpointslist.toarry ());

Four, canvas coordinate translation

Screen coordinates:

The upper-left corner of the screen is the origin, the x-axis is horizontal, and the vertical is the y-axis.

Change the Origin position.
G.translatetransform (dx,dy); // Flip Y-axis g.scaletransform (1,-1);

Use of GDI +