Question

How to know the file size of an image (C# openDialog, window form)

Answer 1

File sizes can be checked using FileInfo.Length.

OpenFileDialog openFileDialog1 = new OpenFileDialog();

openFileDialog1.InitialDirectory = "c:\\" ;
openFileDialog1.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*" ;
openFileDialog1.FilterIndex = 2 ;
openFileDialog1.RestoreDirectory = true ;

if (DialogResult.OK == openFileDialog1.ShowDialog()) 
{
    string file = openFileDialog1.FileName;

    FileInfo fi = new FileInfo(file);
    int fileSize = fi.Length;
}