前言
今天介紹兩個縮圖的 helper，使用的套件是 ImageWorkshop，以下面這兩張圖片解說。
500x300
300x500
程式碼
application/contollers/Image.php
<?php
class Image extends CI_Controller
{
public function index()
{
$this->load->helper('image_helper');
$this->load->view('image');
}
}
application/helpers/image_helper.php
<?php
use PHPImageWorkshop\ImageWorkshop;
if (!function_exists('fit_thumb')) {
function fit_thumb($path, $width = 150, $height = 0)
{
if (!file_exists($path)) {
return 'assets/imgs/file_not_exists.png';
}
if ($height == 0) {
$height = $ratio = $width;
} else {
$ratio = ($width < $height) ? $height : $width;
}
$paths = pathinfo($path);
$thumbName = "{$paths['filename']}_fit_{$width}x{$height}.{$paths['extension']}";
$thumbPath = $paths['dirname'].'/thumb/';
$fullThumbPath = $thumbPath.$thumbName;
if (file_exists($fullThumbPath)) {
return $fullThumbPath;
}
$layer = ImageWorkshop::initFromPath($path, true);
$layer->resizeByLargestSideInPixel($ratio, true);
$layer->cropInPixel($width, $height, 0, 0, 'MT');
$layer->save($thumbPath, $thumbName);
return $fullThumbPath;
}
}
if (!function_exists('thumb')) {
function thumb($path, $ratio = 150, $bySide = 'large')
{
if (!file_exists($path)) {
return 'assets/imgs/file_not_exists.png';
}
$paths = pathinfo($path);
switch ($bySide) {
case 'large':
$thumbName = "{$paths['filename']}_thumb_large_{$ratio}.{$paths['extension']}";
break;
case 'narrow':
$thumbName = "{$paths['filename']}_thumb_narrow_{$ratio}.{$paths['extension']}";
break;
}
$thumbPath = $paths['dirname'].'/thumb/';
$fullThumbPath = $thumbPath.$thumbName;
if (file_exists($fullThumbPath)) {
return $fullThumbPath;
}
$layer = ImageWorkshop::initFromPath($path, true);
switch ($bySide) {
case 'large':
$layer->resizeByLargestSideInPixel($ratio, true);
break;
case 'narrow':
$layer->resizeByNarrowSideInPixel($ratio, true);
break;
}
$layer->save($thumbPath, $thumbName);
return $fullThumbPath;
}
}
if (!function_exists('img_upload')) {
function img_upload($path = '/', $image = '', $maxWidth = 3000)
{
$status = 'done';
$message = '';
$allows = ['jpeg', 'png', 'gif'];
$file = $_FILES[$image];
$fileName = $file['name'];
$ext = pathinfo($fileName, PATHINFO_EXTENSION);
$newName = date('YmdHis').rand(1000, 9999).'.'.$ext;
$map = function ($item) {
return "image/{$item}";
};
try {
if (empty($fileName)) {
throw new Exception('請選擇檔案');
}
$type = $file['type'];
$tmpName = $file['tmp_name'];
if (!in_array($type, array_map($map, $allows))) {
throw new Exception('檔案格式錯誤，僅接受'.implode(', ', $allows));
}
$layer = ImageWorkshop::initFromPath($tmpName, true);
list($width, $height) = getimagesize($tmpName);
if ($width > $maxWidth) {
$layer->resizeInPixel($maxWidth, null, true);
}
$layer->save($path, $newName);
} catch (Exception $e) {
$status = 'fail';
$message = $e->getMessage();
}
return [
'status' => $status,
'image' => $newName,
'message' => $message,
];
}
}
if (!function_exists('image_delete')) {
function image_delete($path, $image)
{
$path = rtrim($path, '/').'/';
@unlink($path.$image);
$fileName = pathinfo($image, PATHINFO_FILENAME);
$thumbPath = $path.'thumb/';
$thumbs = directory_map($thumbPath);
foreach ($thumbs as $thumb) {
$body = explode('_', $thumb)[0];
if ($body === $fileName) {
@unlink($thumbPath.$thumb);
}
}
}
}
application/views/image.php
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Image Helper</title>
</head>
<body>
<h3>500x300</h3>
<img src="<?php echo $landscape; ?>">
<h3>300x500</h3>
<img src="<?php echo $portrait; ?>">
<h3>fit_thumb</h3>
<img src="<?php echo fit_thumb($landscape, 150); ?>">
<img src="<?php echo fit_thumb($landscape, 150, 200); ?>">
<img src="<?php echo fit_thumb($portrait, 150); ?>">
<img src="<?php echo fit_thumb($portrait, 200, 150); ?>">
<h3>thumb</h3>
<img src="<?php echo thumb($landscape, 150); ?>">
<img src="<?php echo thumb($landscape, 150, 'narrow'); ?>">
<img src="<?php echo thumb($portrait, 150); ?>">
<img src="<?php echo thumb($portrait, 150, 'narrow'); ?>">
</body>
</html>
Demo
fit_thumb
fit_thumb 如果沒有帶入第三個參數便會擷取該圖形為正方形，如果有帶入的話便會照比例擷取。
500x300
fit_thumb($landscape, 150)
150x150
fit_thumb($landscape, 150, 200)
150x200
300x500
fit_thumb($portrait, 150)
150x150
fit_thumb($portrait, 200, 150)
200x150
thumb
thumb 功能會依照傳入的比例參數將圖片依照參數等比例縮放，第二個參數可以決定從寬邊還是窄邊做縮放
500x300
thumb($landscape, 150)
150x90
thumb($landscape, 150, 'narrow')
250x150
300x500
thumb($portrait, 150)
90x150
thumb($portrait, 150, 'narrow')
150x250
img_upload
img_upload 這個 function 可以將你上傳的圖片縮圖後存入，一般來說網頁會顧慮的是寬不要破壞，因此程式碼會以寬度為主來做縮圖。
