异步上传到又拍云的实例教程，异步上传实例教程_PHP教程

<input type="file" accept="image/jpg,image/jpeg,image/png,image/gif" id="upload">
<input type="hidden" name="file">

<script type="text/javascript">
function($){
  //上传
  $("#upload").on("change", function () {
  //构造FormData对象并赋值
    var formData = new FormData();
    formData.append("policy", "//controller层传递过来upYun的policy配置");
    formData.append("signature", "//controller层传递过来upyun的signature配置");
    formData.append("file", $("#upload")[0].files[0]);
    $.ajax({
      url : "//处理上传的后端程序地址",
      type : "POST",
      data : formData,
      processData : false,
      contentType : false,
      beforeSend: function () {
        //可以做一些正在上传的效果
      },
      success : function(data) {
        //data，我们这里是异步上传到后端程序所返回的图片地址
      },
      error : function(responseStr) {
        console.log(responseStr);
      }
    });
  });
}($);
</script>