我正在尝试用php和jquery实现一个上传表单,并且现在除了一件我认为很无聊但是还是无法理解的事情外,一切都很好。
让我来解释一下:
实际上,当我运行图片上传时,我会立即在屏幕上打印出一个临时预览,我会在这个预览中裁剪我喜欢的图像,然后保存缩略图。然而,如果我插入高分辨率的jpg,则会看到实际大小,因此对于页面来说太大了。以下是代码:
INDEX.PHP
<?php
function uploadImageFile() { // Note: GD library is required for this function
if ($_SERVER['REQUEST_METHOD'] == 'POST') {
$iWidth = $iHeight = 100; // desired image result dimensions
$iJpgQuality = 90;
if ($_FILES) {
// if no errors and size less than 250kb
if (! $_FILES['image_file']['error'] && $_FILES['image_file']['size'] < 55555250 * 1024) {
if (is_uploaded_file($_FILES['image_file']['tmp_name'])) {
// new unique filename
$sTempFileName = 'cache/' . md5(time().rand());
// move uploaded file into cache folder
move_uploaded_file($_FILES['image_file']['tmp_name'], $sTempFileName);
// change file permission to 644
@chmod($sTempFileName, 0644);
if (file_exists($sTempFileName) && filesize($sTempFileName) > 0) {
$aSize = getimagesize($sTempFileName); // try to obtain image info
if (!$aSize) {
@unlink($sTempFileName);
return;
}
// check for image type
switch($aSize[2]) {
case IMAGETYPE_JPEG:
$sExt = '.jpg';
// create a new image from file
$vImg = @imagecreatefromjpeg($sTempFileName);
break;
/*case IMAGETYPE_GIF:
$sExt = '.gif';
// create a new image from file
$vImg = @imagecreatefromgif($sTempFileName);
break;*/
case IMAGETYPE_PNG:
$sExt = '.png';
// create a new image from file
$vImg = @imagecreatefrompng($sTempFileName);
break;
default:
@unlink($sTempFileName);
return;
}
// create a new true color image
$vDstImg = @imagecreatetruecolor( $iWidth, $iHeight );
// copy and resize part of an image with resampling
imagecopyresampled($vDstImg, $vImg, 0, 0, (int)$_POST['x1'], (int)$_POST['y1'], $iWidth, $iHeight, (int)$_POST['w'], (int)$_POST['h']);
// define a result image filename
$sResultFileName = $sTempFileName . $sExt;
// output image to file
imagejpeg($vDstImg, $sResultFileName, $iJpgQuality);
@unlink($sTempFileName);
return $sResultFileName;
}
}
}
}
}
}
$sImage = uploadImageFile();
echo '<div align=center><img src="'.$sImage.'" /></div>';
echo $sImage;
?>
<!-- add styles -->
<link href="css/main.css" rel="stylesheet" type="text/css" />
<link href="css/jquery.Jcrop.min.css" rel="stylesheet" type="text/css" />
<!-- add scripts -->
<script src="js/jquery.min.js"></script>
<script src="js/jquery.Jcrop.min.js"></script>
<script src="js/script.js"></script>
</head>
<body>
<div class="demo">
<div class="bbody">
<!-- upload form -->
<form id="upload_form" enctype="multipart/form-data" method="post" onsubmit="return checkForm()">
<!-- hidden crop params -->
<input type="hidden" id="x1" name="x1" />
<input type="hidden" id="y1" name="y1" />
<input type="hidden" id="x2" name="x2" />
<input type="hidden" id="y2" name="y2" />
<h2>Step1: Please select image file</h2>
<div><input type="file" name="image_file" id="image_file" onchange="fileSelectHandler()" /></div>
<div class="error"></div>
<div class="step2">
<h2>Step2: Please select a crop region</h2>
<img id="preview"/> <!-- QUESTA È LA PREVIEW -->
<div class="info">
<label>File size</label> <input type="text" id="filesize" name="filesize" />
<label>Type</label> <input type="text" id="filetype" name="filetype" />
<label>Image dimension</label> <input type="text" id="filedim" name="filedim" />
<label>W</label> <input type="text" id="w" name="w" />
<label>H</label> <input type="text" id="h" name="h" />
</div>
<input type="submit" value="Upload" />
</div>
</form>
</div>
</div>
</body>
</html>
SCRIPT.JS
function bytesToSize(bytes) {
var sizes = ['Bytes', 'KB', 'MB'];
if (bytes == 0) return 'n/a';
var i = parseInt(Math.floor(Math.log(bytes) / Math.log(1024)));
return (bytes / Math.pow(1024, i)).toFixed(1) + ' ' + sizes[i];
};
// check for selected crop region
function checkForm() {
if (parseInt($('#w').val())) return true;
$('.error').html('Please select a crop region and then press Upload').show();
return false;
};
// update info by cropping (onChange and onSelect events handler)
function updateInfo(e) {
$('#x1').val(e.x);
$('#y1').val(e.y);
$('#x2').val(e.x2);
$('#y2').val(e.y2);
$('#w').val(e.w);
$('#h').val(e.h);
};
// clear info by cropping (onRelease event handler)
function clearInfo() {
$('.info #w').val('');
$('.info #h').val('');
};
function fileSelectHandler() {
// get selected file
var oFile = $('#image_file')[0].files[0];
// hide all errors
$('.error').hide();
// check for image type (jpg and png are allowed)
var rFilter = /^(image\/jpeg|image\/png)$/i;
if (! rFilter.test(oFile.type)) {
$('.error').html('Please select a valid image file (jpg and png are allowed)').show();
return;
}
// check for file size
if (oFile.size > 55555250 * 1024) {
$('.error').html('You have selected too big file, please select a one smaller image file').show();
return;
}
// preview element
var oImage = document.getElementById('preview');
// prepare HTML5 FileReader
var oReader = new FileReader();
oReader.onload = function(e) {
// e.target.result contains the DataURL which we can use as a source of the image
oImage.src = e.target.result;
oImage.onload = function () { // onload event handler
// display step 2
$('.step2').fadeIn(500);
// display some basic image info
var sResultFileSize = bytesToSize(oFile.size);
$('#filesize').val(sResultFileSize);
$('#filetype').val(oFile.type);
$('#filedim').val(oImage.naturalWidth + ' x ' + oImage.naturalHeight);
// Create variables (in this scope) to hold the Jcrop API and image size
var jcrop_api, boundx, boundy;
// destroy Jcrop if it is existed
if (typeof jcrop_api != 'undefined')
jcrop_api.destroy();
// initialize Jcrop
$('#preview').Jcrop({
minSize: [32, 32], // min crop size
aspectRatio : 1, // keep aspect ratio 1:1
bgFade: true, // use fade effect
bgOpacity: .3, // fade opacity
onChange: updateInfo,
onSelect: updateInfo,
onRelease: clearInfo
}, function(){
// use the Jcrop API to get the real image size
var bounds = this.getBounds();
boundx = bounds[0];
boundy = bounds[1];
// Store the Jcrop API in the jcrop_api variable
jcrop_api = this;
});
};
};
// read selected file as DataURL
oReader.readAsDataURL(oFile);
}
jquey.Jcrop.min.css
/* jquery.Jcrop.min.css v0.9.10 (build:20120429) */
.jcrop-holder{direction:ltr;text-align:left;}
.jcrop-vline,.jcrop-hline{background:#FFF url(Jcrop.gif) top left repeat;font-size:0;position:absolute;}
.jcrop-vline{height:100%;width:1px!important;}
.jcrop-hline{height:1px!important;width:100%;}
.jcrop-vline.right{right:0;}
.jcrop-hline.bottom{bottom:0;}
.jcrop-handle{background-color:#333;border:1px #eee solid;font-size:1px;}
.jcrop-tracker{-webkit-tap-highlight-color:transparent;-webkit-touch-callout:none;-webkit-user-select:none;height:100%;width:100%;}
.jcrop-handle.ord-n{left:50%;margin-left:-4px;margin-top:-4px;top:0;}
.jcrop-handle.ord-s{bottom:0;left:50%;margin-bottom:-4px;margin-left:-4px;}
.jcrop-handle.ord-e{margin-right:-4px;margin-top:-4px;right:0;top:50%;}
.jcrop-handle.ord-w{left:0;margin-left:-4px;margin-top:-4px;top:50%;}
.jcrop-handle.ord-nw{left:0;margin-left:-4px;margin-top:-4px;top:0;}
.jcrop-handle.ord-ne{margin-right:-4px;margin-top:-4px;right:0;top:0;}
.jcrop-handle.ord-se{bottom:0;margin-bottom:-4px;margin-right:-4px;right:0;}
.jcrop-handle.ord-sw{bottom:0;left:0;margin-bottom:-4px;margin-left:-4px;}
.jcrop-dragbar.ord-n,.jcrop-dragbar.ord-s{height:7px;width:100%;}
.jcrop-dragbar.ord-e,.jcrop-dragbar.ord-w{height:100%;width:7px;}
.jcrop-dragbar.ord-n{margin-top:-4px;}
.jcrop-dragbar.ord-s{bottom:0;margin-bottom:-4px;}
.jcrop-dragbar.ord-e{margin-right:-4px;right:0;}
.jcrop-dragbar.ord-w{margin-left:-4px;}
.jcrop-light .jcrop-vline,.jcrop-light .jcrop-hline{background:#FFF;filter:Alpha(opacity=70)!important;opacity:.70!important;}
.jcrop-light .jcrop-handle{-moz-border-radius:3px;-webkit-border-radius:3px;background-color:#000;border-color:#FFF;border-radius:3px;}
.jcrop-dark .jcrop-vline,.jcrop-dark .jcrop-hline{background:#000;filter:Alpha(opacity=70)!important;opacity:.7!important;}
.jcrop-dark .jcrop-handle{-moz-border-radius:3px;-webkit-border-radius:3px;background-color:#FFF;border-color:#000;border-radius:3px;}
.jcrop-holder img,img.jcrop-preview{max-width:none;}
如若不理解,可下载完整脚本。(对我的英语表示抱歉,我是意大利人) 下载链接:http://dfiles.eu/files/6yazp1des
jcp = Jcrop.attach(img, { multi: true }); Jcrop.setOptions({ boxWidth: 500, minSize: [200, 300], }); });`
- Utsav Upadhyay