Question

我的视图中有一个文件

<form id="upload" enctype="multipart/form-data">
   <input type="file" name="fileUpload" id="fileUpload" size="23" />
</form>

和ajax请求

$.ajax({
    url: '<%=Url.Action("JsonSave","Survey")  %>',
    dataType: 'json',
    processData: false,
    contentType: "multipart/mixed",
    data: {
        Id: selectedRow.Id,
        Value: 'some date was added by the user here :))'
    },
    cache: false,
    success: function (data) {}
});

但 Request.Files 中没有文件。 ajax请求有什么问题？

Answer 1

Upload files using AJAX in ASP.Net MVC

自HTML5以来情况发生了变化

<强>的JavaScript

document.getElementById('uploader').onsubmit = function () {
    var formdata = new FormData(); //FormData object
    var fileInput = document.getElementById('fileInput');
    //Iterating through each files selected in fileInput
    for (i = 0; i < fileInput.files.length; i++) {
        //Appending each file to FormData object
        formdata.append(fileInput.files[i].name, fileInput.files[i]);
    }
    //Creating an XMLHttpRequest and sending
    var xhr = new XMLHttpRequest();
    xhr.open('POST', '/Home/Upload');
    xhr.send(formdata);
    xhr.onreadystatechange = function () {
        if (xhr.readyState == 4 && xhr.status == 200) {
            alert(xhr.responseText);
        }
    }
    return false;
}

<强>控制器

public JsonResult Upload()
{
    for (int i = 0; i < Request.Files.Count; i++)
    {
        HttpPostedFileBase file = Request.Files[i]; //Uploaded file
        //Use the following properties to get file's name, size and MIMEType
        int fileSize = file.ContentLength;
        string fileName = file.FileName;
        string mimeType = file.ContentType;
        System.IO.Stream fileContent = file.InputStream;
        //To save file, use SaveAs method
        file.SaveAs(Server.MapPath("~/")+ fileName ); //File will be saved in application root
    }
    return Json("Uploaded " + Request.Files.Count + " files");
}

编辑：HTML

<form id="uploader">
    <input id="fileInput" type="file" multiple>
    <input type="submit" value="Upload file" />
</form>

Answer 2

现在可以通过将FormData对象传递到data请求的$.ajax属性来上传AJAX文件。

由于OP专门要求实现jQuery，所以请转到：

<form id="upload" enctype="multipart/form-data" action="@Url.Action("JsonSave", "Survey")" method="POST">
    <input type="file" name="fileUpload" id="fileUpload" size="23" /><br />
    <button>Upload!</button>
</form>

$('#upload').submit(function(e) {
    e.preventDefault(); // stop the standard form submission

    $.ajax({
        url: this.action,
        type: this.method,
        data: new FormData(this),
        cache: false,
        contentType: false,
        processData: false,
        success: function (data) {
            console.log(data.UploadedFileCount + ' file(s) uploaded successfully');
        },
        error: function(xhr, error, status) {
            console.log(error, status);
        }
    });
});

public JsonResult Survey()
{
    for (int i = 0; i < Request.Files.Count; i++)
    {
        var file = Request.Files[i];
        // save file as required here...
    }
    return Json(new { UploadedFileCount = Request.Files.Count });
}

有关FormData at MDN

的更多信息

Answer 3

你不能通过ajax上传文件，你需要使用iFrame或其他一些技巧来做一个完整的回发。这主要是出于安全考虑。

Here's a decent write-up including a sample project使用Steve Sanderson的SWFUpload和ASP.Net MVC。这是我第一次看到它与Asp.Net MVC一起正常工作（我当时也是MVC的新手），希望它对你有帮助。

Answer 4

如果您使用ajax发布表单，则不能使用$ .ajax方法发送图像，你必须使用经典的xmlHttpobject方法来保存图像，其他替代方法是使用提交类型而不是按钮

Answer 5

我在vuejs版本上有这样的示例：v2.5.2

<form action="url" method="post" enctype="multipart/form-data">
    <div class="col-md-6">
        <input type="file" class="image_0" name="FilesFront" ref="FilesFront" />
    </div>
    <div class="col-md-6">
        <input type="file" class="image_1" name="FilesBack" ref="FilesBack" />
    </div>
</form>
<script>
Vue.component('v-bl-document', {
    template: '#document-item-template',
    props: ['doc'],
    data: function () {
        return {
            document: this.doc
        };
    },
    methods: {
        submit: function () {
            event.preventDefault();

            var data = new FormData();
            var _doc = this.document;
            Object.keys(_doc).forEach(function (key) {
                data.append(key, _doc[key]);
            });
            var _refs = this.$refs;
            Object.keys(_refs).forEach(function (key) {
                data.append(key, _refs[key].files[0]);
            });

            debugger;
            $.ajax({
                type: "POST",
                data: data,
                url: url,
                cache: false,
                contentType: false,
                processData: false,
                success: function (result) {
                    //do something
                },

            });
        }
    }
});
</script>

在asp.net mvc中使用jQuery ajax上传文件

5 个答案: