Graphics.ScaleTransform Method (Single, Single)
Note 

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Applies the specified scaling operation to the transformation matrix of this Graphics by prepending it to the object's transformation matrix.
Assembly: System.Drawing (in System.Drawing.dll)
Parameters
 sx

Type:
System.Single
Scale factor in the x direction.
 sy

Type:
System.Single
Scale factor in the y direction.
The scaling operation consists of multiplying the transformation matrix by a diagonal matrix whose elements are (sx, sy, 1). This method prepends the transformation matrix of the Graphics by the scaling matrix.
The following code example is designed for use with Windows Forms, and it requires PaintEventArgse, which is a parameter of the Paint event handler. The code performs the following actions:
Rotates the world transformation matrix of the Windows Form by 30 degrees.
Scales that matrix by a factor of 3 in the x direction and a factor of 1 in the y direction by prepending the scaling transformation.
Draws a scaled, rotated rectangle with a blue pen.
The result is still a rectangle.
private void ScaleTransformFloat(PaintEventArgs e) { // Set world transform of graphics object to rotate. e.Graphics.RotateTransform(30.0F); // Then to scale, prepending to world transform. e.Graphics.ScaleTransform(3.0F, 1.0F); // Draw scaled, rotated rectangle to screen. e.Graphics.DrawRectangle(new Pen(Color.Blue, 3), 50, 0, 100, 40); }
Available since 1.1