Php determines whether the image format is JPG-PHP source code

Ec (2); in fact, many methods are also very simple, for example, $ _ FILES [userfile] [type] is to judge before the file is uploaded. there is also a getimagesize -- get the image size while getimagesize returns and parameters are as follows. returns an array with four units. Index 0 contains the pixel value of the image width, and index 1 contains the pixel value of the Image Height. Index 2 is the mark of the image type: 1GIF, 2JPG, 3PNG script ec (2); script

In fact, there are many simple methods, such

$ _ FILES ['userfile'] ['type'] is to judge before the file is uploaded.

There is also a getimagesize -- get the image size while getimagesize returns and parameters are as follows.

Returns an array with four units. Index 0 contains the pixel value of the image width, and index 1 contains the pixel value of the Image Height. Index 2 is the mark of the image type: 1 = GIF, 2 = JPG, 3 = PNG, 4 = SWF, 5 = PSD, 6 = BMP, 7 = TIFF (intel byte order), 8 = TIFF (motorola byte order), 9 = JPC, 10 = JP2, 11 = JPX, 12 = JB2, 13 = SWC, 14 = IFF, 15 = WBMP, 16 = XBM. These tags correspond to the newly added IMAGETYPE constant in PHP 4.3.0. Index 3 is a text string with the content "height =" yyy "width =" xxx "and can be directly used for IMG marking.