php method to implement file thumbnails: first create a PHP sample file; then pass "if ($_REQUEST['action']=="add"){...}if ($userfile_size>102400 ){...}" method to create thumbnails from uploaded files.
The operating environment of this article: windows7 system, PHP7.1 version, DELL G3 computer
How does php realize file thumbnails?
php method to create thumbnails from uploaded files
The example of this article describes the method of php to create thumbnails from uploaded files.
The specific implementation method is as follows:
<?php if ($_REQUEST['action']=="add"){ $userfile = $HTTP_POST_FILES['photo']['tmp_name']; $userfile_name = $HTTP_POST_FILES['photo']['name']; $userfile_size = $HTTP_POST_FILES['photo']['size']; $userfile_type = $HTTP_POST_FILES['photo']['type']; ///////////////////////// //GET-DECLARE DIMENSIONS // $dimension = getimagesize($userfile); $large_width = $dimension[0]; // GET PHOTO WIDTH $large_height = $dimension[1]; //GET PHOTO HEIGHT $small_width = 120; // DECLARE THUMB WIDTH $small_height = 90; // DECLARE THUMB HEIGHT ///////////////////////// //CHECK SIZE // if ($userfile_size>102400){ $error=1; $msg = "The photo is over 100kb. Please try again."; } //////////////////////////////// // CHECK TYPE (IE AND OTHERS) // if ($userfile_type="image/pjpeg"){ if ($userfile_type!="image/jpeg"){ $error=1; $msg = "The photo must be JPG"; } } ////////////////////////////// //CHECK WIDTH/HEIGHT // if ($large_width!=600 or$large_height!=400){ $error=1; $msg = "The photo must be 600x400 pixels"; } /////////////////////////////////////////// //CREATE THUMB / UPLOAD THUMB AND PHOTO /// if ($error<>1){ $image = $userfile_name; //if you want to insert it to the database $pic = imagecreatefromjpeg($userfile); $small = imagecreatetruecolor($small_width,$small_height); imagecopyresampled($small,$pic,0,0,0,0, $small_width, $small_height, $large_width, $large_height); if (imagejpeg($small,"path/to/folder/to/upload/thumb".$userfile_name, 100)){ $large = imagecreatetruecolor($large_width,$large_height); imagecopyresampled($large,$pic,0,0,0,0, $large_width, $large_height, $large_width, $large_height); if (imagejpeg($large,"path/to/folder/to/upload/photo".$userfile_name, 100)) {} else {$msg="A problem has occured. Please try again."; $error=1;} } else { $msg="A problem has occured. Please try again."; $error=1; } } ////////////////////////////////////////////// /// If everything went right a photo (600x400) and /// a thumb(120x90) were uploaded to the given folders } ?> <html><head><title>create thumb</title></head> <body> <form name="form1" enctype="multipart/form-data" action="thisfile.php?action=add" method="post"> Select Photo: <input type="file" name="photo"> <input type="submit" name="submit" value="CREATE THUMB AND UPLOAD"> </form> </body </html>
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