我的目标是将一些图像上传到服务器并为它们提供描述。
单击上传按钮时,这就是我想要发生的事情:
1)一个javascript函数动态添加一个表单来获取图像的描述。
2) 提交表格时:
a) the description entered in the form must be available $_POST['description'] at server side. b) the images are sent to the server using an XMLHttpRequest
在我编写的代码中,描述不可用$_POST['description']
。当我删除检查if(!isset($_POST['description']))
时,图像文件已完美上传。这是我的代码:
javascript代码
upload.onclick = uploadPrompt;
// dynamically add a form
function uploadPrompt () {
// fileQueue is an array containing all images that need to be uploaded
if (fileQueue.length < 1) {
alert("There are no images available for uploading.");
} else {
var inputDescription = document.createElement("input");
inputDescription.className = "promptInput";
inputDescription.type = "text";
inputDescription.name = "description";
var inputButton = document.createElement("button");
inputButton.id = "promptInputButton";
inputButton.type = "submit";
inputButton.innerHTML = "Start uploading";
var promptForm = document.createElement("form");
promptForm.method = "post";
promptForm.action = "upload.php";
promptForm.onsubmit = uploadQueue;
promptForm.id = "promptForm";
promptForm.appendChild(inputDescription);
promptForm.appendChild(inputButton);
document.body.appendChild(promptForm);
}
}
function uploadQueue(ev) {
ev.preventDefault();
elementToBeRemoved = document.getElementById("promptForm");
elementToBeRemoved.parentElement.removeChild(elementToBeRemoved);
while (fileQueue.length > 0) {
var item = fileQueue.pop();
// item.file is the actual image data
uploadFile(item.file);
}
}
function uploadFile (file) {
if (file) {
var xhr = new XMLHttpRequest();
var fd = new FormData();
fd.append('image',file);
xhr.upload.addEventListener("error", function (ev) {
console.log(ev);
}, false);
xhr.open("POST", "upload.php");
xhr.setRequestHeader("Cache-Control", "no-cache");
xhr.setRequestHeader("X-Requested-With", "XMLHttpRequest");
xhr.setRequestHeader("X-File-Name", file.name);
xhr.send(fd);
}
}
php代码上传.php
<?php
session_start();
if (!isset($_POST['description'])) {
echo "upload:fail\n";
echo "message:No scene was specified";
exit();
}
if (isset($_FILES['image'])) {
if(!move_uploaded_file($_FILES['image']['tmp_name'], "uploads/" . $_POST['description'] . "/" . $_FILES['image']['name'])) {
echo "upload:fail\n";
}
else {
echo "upload:succes\n";
}
exit();
}
exit();
?>