本文实例讲述了php修改上传图片尺寸的方法。分享给大家供大家参考。具体实现方法如下：

<?php// This is the temporary file created by PHP$uploadedfile = $_FILES['uploadfile']['tmp_name'];// Create an Image from it so we can do the resize$src = imagecreatefromjpeg($uploadedfile);// Capture the original size of the uploaded imagelist($width,$height)=getimagesize($uploadedfile);// For our purposes, I have resized the image to be// 600 pixels wide, and maintain the original aspect// ratio. This prevents the image from being "stretched"// or "squashed". If you prefer some max width other than// 600, simply change the $newwidth variable$newwidth=600;$newheight=($height/$width)*600;$tmp=imagecreatetruecolor($newwidth,$newheight);// this line actually does the image resizing, copying from the original// image into the $tmp imageimagecopyresampled($tmp,$src,0,0,0,0,$newwidth,$newheight,$width,$height);// now write the resized image to disk. I have assumed that you want the// resized, uploaded image file to reside in the ./images subdirectory.$filename = "images/". $_FILES['uploadfile']['name'];imagejpeg($tmp,$filename,100);imagedestroy($src);imagedestroy($tmp);// NOTE: PHP will clean up the temp file it created when the request// has completed.?>

希望本文所述对大家的php程序设计有所帮助。