根据设备的宽度和高度调整图像大小

Question

I am trying to resize an image in asp.net Visual studio V2008, c#

using (Graphics newgraphics = Graphics.FromImage(myBackgroundImage))
{
newgraphics.Clear(Color.FromArgb(-1));
if ((float)oldbmp.Width / (float)Width == (float)oldbmp.Height / (float)Height)            
  {
    newgraphics.DrawImage(oldbmp, 0, 0, Width, Height);
  }
} 

I have entered the above code, but I get the following errors on a build.

the Graphic.DrawImage is overloaded. It is expecting , int, int, Rectangle, graphicsunit

Anyone have any suggestions?

Much appreciated
Rachael

Answer 1

Based on the error message you've provided, it seems like you are not providing the correct arguments for DrawImage method.

Can you confirm what type 'oldbmp' belongs to ? It should be an 'Image' type in order to satisfy one of the overload requirements.

Below is all the overloads for DrawImage method.

http://msdn.microsoft.com/en-us/library/system.drawing.graphics.drawimage(v=vs.110).aspx

Based on your code, below overload should do the job.

http://msdn.microsoft.com/en-us/library/2ab36azw(v=vs.110).aspx

Have you tried using 0.0F instead of 0 ?

Answer 2

I have solved this issue

• In InitializeComponent I added the following two lines

\n        'this.AutoScaleDimensions = new System.Drawing.SizeF(96F, 96F);' \n        'this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Dpi;' \n    

This explains why I did that CLick Here

• I attached the image to the form Skin - As it was currently being draw in the paint override method - The code above does not re-size images drawn in the paint override method

• Set the sizemode to Stretch Image and then will check the DPI of the device and reset the image accordingly

That should do the trick

Thanks jundev for your patient.