PHP generates thumbnail illustration sample code sharing

Share a use of PHP's GD library to generate thumbnails of examples, we refer to the use of the bar

The code is as follows:

<form method= "POST" action= "suo_do.php" enctype= "Multipart/form-data" >

<input type= "file" name= "Pic"/>

<input type= "Submit" value= "Upload 1"/>

</form>

<?php

Header ("CONTENT-TYPE:TEXT/HTML;CHARSET=GBK");

Ini_set ("Date.timezone", "Asia/chong");

Determine if the file is empty

if (empty ($_files)) {

echo "Upload file too large";

Exit

}

To determine if there are errors in file uploads

if ($_files[' pic '] [' ERROR ']) {

echo "Upload file";

Exit

}

To determine if a file type illegally obtains a file suffix

$allowtype =array ("JPG", "PNG", "JPEG", "gif");

$a =explode ('. ', $_files[' pic '] [' name ']);

$index =count ($a)-1;

$ex =strtolower ($a [$index]);

if (!in_array ($ex, $allowtype)) {

echo "Illegal upload file";

Exit

}

$file =date (' Ymdhis '). Rand (). "." $ex;

$SRC =$_files[' pic '] [' tmp_name '];

$des = "upload/". $file;

$rs =move_uploaded_file ($SRC, $des);

Thumbnail image

Read already uploaded pictures

$image =imagecreatefromjpeg ($des);

$a =getimagesize ($des);

$w = $a [0];

$h = $a [1];

if ($w > $h) {

$width = 300;

$height = $width/$w * $H;

}else if ($w < $h) {

$height = 300;

$width = $height/$h * $W;

}else{

$width = 300;

$height = 300;

} www.jbxue.com

Create a blank new picture

$newimage =imagecreatetruecolor ($width, $height);

Copy source picture content copy new picture

Imagecopyresized ($newimage, $image, 0,0, 0,0, $width, $height, $w, $h);

$filename = "Upload/s_". $file;

Imagejpeg ($newimage, $filename);