use form upload images

[searain]

1) in php, how can i use a form to upload images to the web site?

2) how can i control the size of the images which will be loaded?

3) how can i control the width and length of the images which will be loaded?

4) how can i make sure the uploading file is ".gif or jpg"?

5) how can i make sure that the uploading file is not executable?

6) any other extra securuity approaches i can do to make sure that the uploading files are not executable, (such as set the files under the folder not executable, etc.)

thanks, any people help me out!

[MrAlaska]

All your questions are answered on one page in the manual, including sample scripts.
http://www.php.net/manual/en/features.file-upload.php

There a some issues you might run into, like possibly needing to manually set write permissions on the upload folder if you are running PHP in safe mode.

Here is a list of validation types that will work for images. Tuck them away for when you are ready:

//all image types to upload
$cert1 = "image/pjpeg"; //Jpeg type 1
$cert2 = "image/jpeg"; //Jpeg type 2
$cert3 = "image/gif"; //Gif type
$cert4 = "image/ief"; //Ief type
$cert5 = "image/png"; //Png type
$cert6 = "image/tiff"; //Tiff type
$cert7 = "image/bmp"; //Bmp Type
$cert8 = "image/vnd.wap.wbmp"; //Wbmp type
$cert9 = "image/x-cmu-raster"; //Ras type
$cert10 = "image/x-x-portable-anymap"; //Pnm type
$cert11 = "image/x-portable-bitmap"; //Pbm type
$cert12 = "image/x-portable-graymap"; //Pgm type
$cert13 = "image/x-portable-pixmap"; //Ppm type
$cert14 = "image/x-rgb"; //Rgb type
$cert15 = "image/x-xbitmap"; //Xbm type
$cert16 = "image/x-xpixmap"; //Xpm type
$cert17 = "image/x-xwindowdump"; //Xwd type