Question about bitmap saving in .NET

Question

I have a bitmap object and draw some curves on it by setpixel method. when I save this bitmap as jpg file, the background of my picture is not a white surface. the background is transparent. what is the problem? How can I resolve this problem?

Accepted Answer

Call `Graphics.Clear(Color.White)` before you draw on the bitmap. If you do not already have an instance of `System.Drawing.Graphics` for your bitmap, here's how to get one:

```
Graphics g = Graphics.FromImage(bitmap);
```

Clear the bitmap:

```
g.Clear(Color.White);
```

And of course, don't forget to call `Dispose()` when you are done with the graphics.

```
g.Dispose();
```

Question about bitmap saving in .NET

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