Check out example codes for "windows forms picturebox has image". It will help you in understanding the concepts better.

Code Example 1

if (pictureBox1.Image != null)
{
    Common.MessageBoxUtilities.WarningMessageBox("You Have Image");
}
else if (pictureBox1.Image == null)
{
    Common.MessageBoxUtilities.WarningMessageBox("You Dont Have Image");
}

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