listbox getting frequently loaded

See more:

C#

i have a bitmap in which i am taking only 9 pixels.

each pixel will have rgb value...i have created an array of 3 * 3 size.

each pixel rgb value is taken separately and loaded in a list box.

after all iterations the no of values in list box will be 27...

till here it is fine.

when i run the application ,,,the listbox gets loaded with all 27 values..but after some 10 to 15 secons...i c the count is increasing again to to 54...sometimes 81...and so on...why is this happening

i have taken the bmp in a picture box..in the form...the code is written in picturebox_paint event...is this a mistake...

first when R is calculated for fist pixel it will go to a function called add...from picturebox1_paint event..where the listbox will get added with R value..and then goes to loop again...similarily for G and B values.

here is the brief code:

pictureBox1_Paint event
{
for (i = 0; i < 3; i++)
{

for (j = 0; j < 3; j++)
{
Color pixelColor = bm.GetPixel(i, j);
b = pixelColor.R;
ADDINARRAY(b);

c = pixelColor.G;
ADDINARRAY(c);
d = pixelColor.B;
ADDINARRAY(d);






}
}
}


// this is the code for items to get loaded in listbox
void ADDINARRAY(int value)
{

listBox1.Items.Add(value);
}