Asp.Net Mvc异步上传文件的方式

时间:2021-01-05 20:12:48

今天试了下mvc自带的ajax,发现上传文件时后端action接收不到文件, Request.Files和HttpPostedFileBase都接收不到。。。。。后来搜索了下才知道mvc自带的Ajax不支持文件上传,无奈之下只能用其他的方式

第一种方式:通过 jquery的ajaxSubmit   ---》(先引入jQuery脚本)需要引入jquery.form.min.js(可以通过NuGet下载)  直接上代码

@{
Layout = null;
} <!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width" />
<title>Index</title>
<script src="~/Scripts/jquery-1.10.2.min.js"></script>
@*<script src="~/Scripts/jquery.unobtrusive-ajax.min.js"></script>*@
@*用了jquery.form.min.js可以不引用,即便引用了也没关系不影响,但是引用了的话需要注意的是会发生两次提交,在提交前执行return false即可,*@
<script src="~/Scripts/jquery.form.min.js"></script>
</head>
<body>
<div>
<h3>mvc异步上传文件</h3>
@using (Ajax.BeginForm("UpFileload", "AjaxFileUpload", new AjaxOptions
{
Confirm = "确认上传吗?",
HttpMethod = "post",
OnSuccess = "func",
}, new { enctype = "multipart/form-data", id = "fileForm" }))
{
<input type="file" name="file" value="" />
@*<button type="submit">异步上传</button>*@
<button type="button">异步上传</button>
}
</div>
</body>
</html>
<script>
//当按钮被点击时执行异步提交
$("button[type=button]").click(() => {
//异步提交
$("#fileForm").ajaxSubmit({
url: "@Url.Action("UpFileload", "AjaxFileUpload")",
type: "post",
success: data => {
alert(data);
},
error: () => {
alert("出错了");
}
});
});
</script>

 后端action代码:

   /// <summary>
/// 异步文件上传
/// </summary>
/// <param name="file">前端上传的文件</param>
/// <returns>文件路径</returns>
public ActionResult UpFileload(HttpPostedFileBase file)
{
//var myfile = Request.Files["file"]; //也可以拿到
var path = $"/UploadFile/{Guid.NewGuid() + file.FileName}";
file.SaveAs(Server.MapPath(path)); //保存文件
return Content(path);
}

jQuery的ajaxSubmit方法和ajax用法都差不多

 第二种方式: $.ajaxFileUpload({})  --->(先引入jQuery脚本)需要引入ajaxfileupload.js脚本  (这个方法是之前在项目过中用过的,不过当时我记得从网上下载下来的ajaxfileupload脚本会提示出错,好像是因为脚本里缺少什么函数来着,忘记了,然后我按照搜索到的解决方法修改了脚本

因为是之前写的项目不是demo,代码量有点多就不一一贴上代码了,其实用法和第一种差不多,

 $.ajaxFileUpload({
url: '@Url.Action("FileUpload", "Profile")',
secureuri: false,
fileElementId: 'btn_file', //文件input标签id
data: null,
success: function (data, status) {
$.post("@Url.Action("MyData", "Profile")", null,
html => {
$("#mybody").children().remove();
$(html).appendTo("#mybody");
});
},
error: function (data, status, e) {
console.log('Error')
}
});

最后贴上修改后的ajaxfileupload.js脚本的源码:

jQuery.extend({

    handleError: function (s, xhr, status, e) {
// If a local callback was specified, fire it
if (s.error) {
s.error.call(s.context || s, xhr, status, e);
} // Fire the global callback
if (s.global) {
(s.context ? jQuery(s.context) : jQuery.event).trigger(
"ajaxError", [xhr, s, e]);
}
}, createUploadIframe: function(id, uri)
{
//create frame
var frameId = 'jUploadFrame' + id; if(window.ActiveXObject) {
var io = document.createElement('<iframe id="' + frameId + '" name="' + frameId + '" />');
if(typeof uri== 'boolean'){
io.src = 'javascript:false';
}
else if(typeof uri== 'string'){
io.src = uri;
}
}
else {
var io = document.createElement('iframe');
io.id = frameId;
io.name = frameId;
}
io.style.position = 'absolute';
io.style.top = '-1000px';
io.style.left = '-1000px'; document.body.appendChild(io); return io
},
createUploadForm: function(id, fileElementId)
{
//create form
var formId = 'jUploadForm' + id;
var fileId = 'jUploadFile' + id;
var form = $('<form action="" method="POST" name="' + formId + '" id="' + formId + '" enctype="multipart/form-data"></form>');
var oldElement = $('#' + fileElementId);
var newElement = $(oldElement).clone();
$(oldElement).attr('id', fileId);
$(oldElement).before(newElement);
$(oldElement).appendTo(form);
//set attributes
$(form).css('position', 'absolute');
$(form).css('top', '-1200px');
$(form).css('left', '-1200px');
$(form).appendTo('body');
return form;
},
addOtherRequestsToForm: function(form,data)
{
// add extra parameter
var originalElement = $('<input type="hidden" name="" value="">');
for (var key in data) {
name = key;
value = data[key];
var cloneElement = originalElement.clone();
cloneElement.attr({'name':name,'value':value});
$(cloneElement).appendTo(form);
}
return form;
}, ajaxFileUpload: function(s) {
// TODO introduce global settings, allowing the client to modify them for all requests, not only timeout
s = jQuery.extend({}, jQuery.ajaxSettings, s);
var id = new Date().getTime()
var form = jQuery.createUploadForm(id, s.fileElementId);
if ( s.data ) form = jQuery.addOtherRequestsToForm(form,s.data);
var io = jQuery.createUploadIframe(id, s.secureuri);
var frameId = 'jUploadFrame' + id;
var formId = 'jUploadForm' + id;
// Watch for a new set of requests
if ( s.global && ! jQuery.active++ )
{
jQuery.event.trigger( "ajaxStart" );
}
var requestDone = false;
// Create the request object
var xml = {}
if ( s.global )
jQuery.event.trigger("ajaxSend", [xml, s]);
// Wait for a response to come back
var uploadCallback = function(isTimeout)
{
var io = document.getElementById(frameId);
try
{
if(io.contentWindow)
{
xml.responseText = io.contentWindow.document.body?io.contentWindow.document.body.innerHTML:null;
xml.responseXML = io.contentWindow.document.XMLDocument?io.contentWindow.document.XMLDocument:io.contentWindow.document; }else if(io.contentDocument)
{
xml.responseText = io.contentDocument.document.body?io.contentDocument.document.body.innerHTML:null;
xml.responseXML = io.contentDocument.document.XMLDocument?io.contentDocument.document.XMLDocument:io.contentDocument.document;
}
}catch(e)
{
jQuery.handleError(s, xml, null, e);
}
if ( xml || isTimeout == "timeout")
{
requestDone = true;
var status;
try {
status = isTimeout != "timeout" ? "success" : "error";
// Make sure that the request was successful or notmodified
if ( status != "error" )
{
// process the data (runs the xml through httpData regardless of callback)
var data = jQuery.uploadHttpData( xml, s.dataType );
// If a local callback was specified, fire it and pass it the data
if ( s.success )
s.success( data, status ); // Fire the global callback
if( s.global )
jQuery.event.trigger( "ajaxSuccess", [xml, s] );
} else
jQuery.handleError(s, xml, status);
} catch(e)
{
status = "error";
jQuery.handleError(s, xml, status, e);
} // The request was completed
if( s.global )
jQuery.event.trigger( "ajaxComplete", [xml, s] ); // Handle the global AJAX counter
if ( s.global && ! --jQuery.active )
jQuery.event.trigger( "ajaxStop" ); // Process result
if ( s.complete )
s.complete(xml, status); jQuery(io).unbind() setTimeout(function()
{ try
{
$(io).remove();
$(form).remove(); } catch(e)
{
jQuery.handleError(s, xml, null, e);
} }, ) xml = null }
}
// Timeout checker
if ( s.timeout > )
{
setTimeout(function(){
// Check to see if the request is still happening
if( !requestDone ) uploadCallback( "timeout" );
}, s.timeout);
}
try
{
// var io = $('#' + frameId);
var form = $('#' + formId);
$(form).attr('action', s.url);
$(form).attr('method', 'POST');
$(form).attr('target', frameId);
if(form.encoding)
{
form.encoding = 'multipart/form-data';
}
else
{
form.enctype = 'multipart/form-data';
}
$(form).submit(); } catch(e)
{
jQuery.handleError(s, xml, null, e);
}
if(window.attachEvent){
document.getElementById(frameId).attachEvent('onload', uploadCallback);
}
else{
document.getElementById(frameId).addEventListener('load', uploadCallback, false);
}
return {abort: function () {}}; }, uploadHttpData: function( r, type ) {
var data = !type;
data = type == "xml" || data ? r.responseXML : r.responseText;
// If the type is "script", eval it in global context
if ( type == "script" )
jQuery.globalEval( data );
// Get the JavaScript object, if JSON is used.
if ( type == "json" )
{
// If you add mimetype in your response,
// you have to delete the '<pre></pre>' tag.
// The pre tag in Chrome has attribute, so have to use regex to remove
var data = r.responseText;
var rx = new RegExp("<pre.*?>(.*?)</pre>","i");
var am = rx.exec(data);
//this is the desired data extracted
var data = (am) ? am[] : ""; //the only submatch or empty
eval( "data = " + data );
}
// evaluate scripts within html
if ( type == "html" )
jQuery("<div>").html(data).evalScripts();
//alert($('param', data).each(function(){alert($(this).attr('value'));}));
return data;
}
})

感觉还是第一种比较舒服~~~不知道还有没有更简单好用的方式