php ajax实现文件上传进度条

本实例是关于php文件上传时进度条的实现，主要采用ajax技术，另外还运用了html5，有需要的朋友可以研究一下。
本实例有两个文件：

upload_form.html：

<!DOCTYPE html>
<html>
<head>
<script>
function _(el){
  return document.getElementById(el);
}
function uploadFile(){
  var file = _("file1").files[0];
  // alert(file.name+" | "+file.size+" | "+file.type);
  var formdata = new FormData();
  formdata.append("file1", file);
  var ajax = new XMLHttpRequest();
  ajax.upload.addEventListener("progress", progressHandler, false);
  ajax.addEventListener("load", completeHandler, false);
  ajax.addEventListener("error", errorHandler, false);
  ajax.addEventListener("abort", abortHandler, false);
  ajax.open("POST", "file_upload_parser.php");
  ajax.send(formdata);
}

function progressHandler(event){
  _("loaded_n_total").innerHTML = "Uploaded "+event.loaded+" bytes of "+event.total;
  var percent = (event.loaded / event.total) * 100;
  _("progressBar").value = Math.round(percent);
  _("status").innerHTML = Math.round(percent)+"% uploaded... please wait";
}

function completeHandler(event){
  _("status").innerHTML = event.target.responseText;
  _("progressBar").value = 0;
}

function errorHandler(event){
  _("status").innerHTML = "Upload Failed";
}

function abortHandler(event){
  _("status").innerHTML = "Upload Aborted";
}
</script>
</head>
<body>
<h2>HTML5 File Upload Progress Bar Tutorial</h2>
<form id="upload_form" enctype="multipart/form-data" method="post">
 <input type="file" name="file1" id="file1"><br>
 <input type="button" value="Upload File" onclick="uploadFile()">
 <progress id="progressBar" value="0" max="100" style="width:300px;"></progress>
 <h3 id="status"></h3>
 <p id="loaded_n_total"></p>
</form>
</body>
</html>

file_upload_parser.php：

<?php
$fileName = $_FILES["file1"]["name"]; // The file name
$fileTmpLoc = $_FILES["file1"]["tmp_name"]; // File in the PHP tmp folder
$fileType = $_FILES["file1"]["type"]; // The type of file it is
$fileSize = $_FILES["file1"]["size"]; // File size in bytes
$fileErrorMsg = $_FILES["file1"]["error"]; // 0 for false... and 1 for true
if (!$fileTmpLoc) { // if file not chosen
  echo "ERROR: Please browse for a file before clicking the upload button.";
  exit();
}
if(move_uploaded_file($fileTmpLoc, "test_uploads/$fileName")){
  echo "$fileName upload is complete";
} else {
  echo "move_uploaded_file function failed";
}
?>

以上就是本文的全部内容，希望对大家的学习有所帮助。