我有一个允许用户上传图像的 jQuery 函数。诚然，我对 jQuery 知之甚少，但我需要能够稍微更改此代码。目前，如果使用不是图像的文件，它会抛出错误，但我希望它抛出错误是该文件不是 jpg、JPG、jpeg 或 JPEG。
我不确定需要多少原始代码，但这是进行过滤的部分。
$(document).ready(function() {
// Makes sure the dataTransfer information is sent when we
// Drop the item in the drop box.
jQuery.event.props.push('dataTransfer');
var z = -40;
// The number of images to display
var maxFiles = 5;
var errMessage = 0;
// Get all of the data URIs and put them in an array
var dataArray = [];
// Bind the drop event to the dropzone.
$('#drop-files').bind('drop', function(e) {
// Stop the default action, which is to redirect the page
// To the dropped file
var files = e.dataTransfer.files;
var ext = $('#drop-files').val().split('.').pop().toLowerCase();
// Show the upload holder
$('#uploaded-holder').show();
// For each file
$.each(files, function(index, file) {
// Some error messaging
if (!files[index].type.match('image.*')) {
if(errMessage == 0) {
$('#drop-files').html('Only jpg files are allowed');
}
return false;
}
// Check length of the total image elements
if($('#dropped-files > .image').length < maxFiles) {
// Change position of the upload button so it is centered
var imageWidths = ((220 + (40 * $('#dropped-files > .image').length)) / 2) - 20;
$('#upload-button').css({'left' : imageWidths+'px', 'display' : 'block'});
}
// Start a new instance of FileReader
var fileReader = new FileReader();
// When the filereader loads initiate a function
fileReader.onload = (function(file) {
return function(e) {
// Push the data URI into an array
dataArray.push({name : file.name, value : this.result});
// Move each image 40 more pixels across
z = z+40;
var image = this.result;
// Just some grammatical adjustments
if(dataArray.length == 1) {
$('#upload-button span').html("1 file to be uploaded");
} else {
$('#upload-button span').html(dataArray.length+" files to be uploaded");
}
// Place extra files in a list
if($('#dropped-files > .image').length < maxFiles) {
// Place the image inside the dropzone
$('#dropped-files').append('<div class="image" style="left: '+z+'px; background: url('+image+'); background-size: cover;"> </div>');
}
else {
$('#extra-files .number').html('+'+($('#file-list li').length + 1));
// Show the extra files dialogue
$('#extra-files').show();
// Start adding the file name to the file list
$('#extra-files #file-list ul').append('<li>'+file.name+'</li>');
}
};
})(files[index]);
// For data URI purposes
fileReader.readAsDataURL(file);
});
});
function restartFiles() {
// This is to set the loading bar back to its default state
$('#loading-bar .loading-color').css({'width' : '0%'});
$('#loading').css({'display' : 'none'});
$('#loading-content').html(' ');
// --------------------------------------------------------
// We need to remove all the images and li elements as
// appropriate. We'll also make the upload button disappear
$('#upload-button').hide();
$('#dropped-files > .image').remove();
$('#extra-files #file-list li').remove();
$('#extra-files').hide();
$('#uploaded-holder').hide();
// And finally, empty the array/set z to -40
dataArray.length = 0;
z = -40;
return false;
}
$('#upload-button .upload').click(function() {
$("#loading").show();
var totalPercent = 100 / dataArray.length;
var x = 0;
var y = 0;
$('#loading-content').html('Uploading '+dataArray[0].name);
$.each(dataArray, function(index, file) {
$.post('upload.php', dataArray[index], function(data) {
var fileName = dataArray[index].name;
++x;
// Change the bar to represent how much has loaded
$('#loading-bar .loading-color').css({'width' : totalPercent*(x)+'%'});
if(totalPercent*(x) == 100) {
// Show the upload is complete
$('#loading-content').html('Uploading Complete!');
window.location = "http://www.dentaldigs.co.uk/upload_success.php";
// Reset everything when the loading is completed
setTimeout(restartFiles, 500);
} else if(totalPercent*(x) < 100) {
// Show that the files are uploading
$('#loading-content').html('Uploading '+fileName);
}
// Show a message showing the file URL.
var dataSplit = data.split(':');
if(dataSplit[1] == 'upload successful') {
var realData = '<li><a href="images/'+dataSplit[0]+'">'+fileName+'</a> '+dataSplit[1]+'</li>';
$('#uploaded-files').append('<li><a href="images/'+dataSplit[0]+'">'+fileName+'</a> '+dataSplit[1]+'</li>');
// Add things to local storage
if(window.localStorage.length == 0) {
y = 0;
} else {
y = window.localStorage.length;
}
window.localStorage.setItem(y, realData);
} else {
$('#uploaded-files').append('<li><a href="images/'+data+'. File Name: '+dataArray[index].name+'</li>');
}
});
});
return false;
});
// Just some styling for the drop file container.
$('#drop-files').bind('dragenter', function() {
$(this).css({'box-shadow' : 'inset 0px 0px 20px rgba(0, 0, 0, 0.1)', 'border' : '4px dashed #B3C234'});
return false;
});
$('#drop-files').bind('drop', function() {
$(this).css({'box-shadow' : 'none', 'border' : '4px dashed rgba(0, 0, 0, 0.1)'});
return false;
});
// Let them know that they aren’t in the correct dragenter zone
$('#drop-files').bind('dragleave', function() {
$(this).css({'box-shadow' : 'none', 'border' : '4px dashed rgba(0,0,0,0.2)'});
return false;
});
// For the file list
$('#extra-files .number').toggle(function() {
$('#file-list').show();
}, function() {
$('#file-list').hide();
});
$('#dropped-files #upload-button .delete').click(restartFiles);
// Append the localstorage the the uploaded files section
if(window.localStorage.length > 0) {
$('#uploaded-files').show();
for (var t = 0; t < window.localStorage.length; t++) {
var key = window.localStorage.key(t);
var value = window.localStorage[key];
// Append the list items
if(value != undefined || value != '') {
$('#uploaded-files').append(value);
}
}
} else {
$('#uploaded-files').hide();
}
});
目前这将允许任何图像类型，我需要它只允许 jpg、JPG、jpeg 和 JPEG