I'm receiving from socket communication an image
as byte[]
and then I try to show it in a pictureBox
. When I run the code it shows a message error only saying: "NullReferenceException"
The catch handling the exception is ex1
and I checked and the pic
isn't null
so I can't figure it out why this exception is happening.
This is my code:
try
{
if (pictureBox1.InvokeRequired)
{
try
{
pic = imageEmp;
addControlHandler c = new addControlHandler(addPic);
this.Invoke(c);
}
catch (Exception exc) { MessageBox.Show(exc.Message); }
}
else
{
pictureBox1.Image = ByteToImage(imageEmp);
}
}
catch (Exception ex1)
{
MessageBox.Show(ex1.Message);
}
public void addPic() //when invokeRequired == true
{
pictureBox1.Image = ByteToImage(pic);
}
Here is the code to convert byte[]
to Image
:
public Image ByteToImage(byte[] imageBytes) //convert byte[] to image
{
MemoryStream ms = new MemoryStream(imageBytes, 0, imageBytes.Length);
ms.Write(imageBytes, 0, imageBytes.Length);
Image image = new Bitmap(ms);
return image;
}
UPDATE 1: Regarding Hans answer, I make he following changes:
Change my ByteToImage to Hans's answer and to check where the error is I added this lines in the place where this.Invoke(c)
was:
if (c != null)
{
try
{
this.Invoke(c);
}
catch (Exception e_c)
{
MessageBox.Show(e_c.Message, "exc from e_c");
}
}
This give me an exception : NullReferenceException
Thanks for any help!
UPDATE 2: Now it's working, I send JPEG images instead of JPG and it show it now. Don't know why this happens but now it's working ok.
Here is an example that you can try I have tested this just now using my own method this works so replace your code with the lines of code in my btnStudentPic_Click let me know if this works for you..
For Compact Framework try this instead
public static byte[] ReadAllBytes(string path)
{
byte[] buffer;
using (FileStream fs = new FileStream(path, FileMode.Open,
FileAccess.Read, FileShare.Read))
{
int offset = 0;
int count = (int)fs.Length;
buffer = new byte[count];
while (count > 0)
{
int bytesRead = fs.Read(buffer, offset, count);
offset += bytesRead;
count -= bytesRead;
}
}
return buffer;
}
//Windows example below don't use for CF
private void btnStudentPic_Click(object sender, EventArgs e)
{
Image picture = (Image)BrowseForPicture();
this.picStudent.Image = picture;
this.picStudent.SizeMode = PictureBoxSizeMode.StretchImage;
}
/// <summary>
///
/// </summary>
/// <returns></returns>
private Bitmap BrowseForPicture()
{
// Bitmap picture = null;
try
{
if (this.fdlgStudentPic.ShowDialog() == DialogResult.OK)
{
byte[] imageBytes = File.ReadAllBytes(this.fdlgStudentPic.FileName);
StudentPic = new Bitmap( this.fdlgStudentPic.FileName);
StuInfo.StudentPic = imageBytes;
}
else
{
StudentPic = Properties.Resources.NoPhotoAvailable;
}
}
catch (Exception)
{
MessageBox.Show("That was not a picture.", "Browse for picture");
StudentPic = this.BrowseForPicture();
}
return StudentPic;
}