Question

我想下载文件，这是早期但是作为byte []（sql中的varbinary（max））进入数据库，但是当我尝试调用DownloadCv方法时，我得到异常： “输入数据不是有效的base-64字符串。”

你能帮我找到我的错误或者显示另一种下载文件的方法吗？欢呼声。

以下是我目前的情况：

public class ApplyForm
{
    /*Some other properties
        ...
    */
    public int FileSize { get; set; }
    public string FileName { get; set; }
    public byte[] FileData { get; set; }
    public string ContentType { get; set; }
}

//应用视图

@model SourceTreeITMatchmaking.Core.Model.ApplyForm

@{
    ViewBag.Title = "Apply";
    Layout = "~/Views/Shared/_Layout.cshtml";
}

    <div>
        <!-- Some properties to bind to ApplyForm are not shown here to avoid misunderstandings-->
        <input class="form-control col-md-2" type="file" name="file" />
        <input class="form-control col-md-2" type="submit" value="Upload" />
        <input type="hidden" name="jobOfferId" value="@Model.TargetOfferId" />
    </div>

//发布表单后应用操作

[HttpPost]
public ActionResult Apply(HttpPostedFileBase file, ApplyForm applyForm, int jobOfferId)
{
    if (file.ContentLength > 0)
    {
        applyForm.FileName = file.FileName;
        applyForm.FileSize = file.ContentLength;
        applyForm.FileData = GetFileBytes(file);
        applyForm.ContentType = file.ContentType;

        dbConnection.ApplyForms.Add(applyForm);
        dbConnection.SaveChanges();

        return RedirectToAction("JobList", "JobOffer");
    }
}

//从HttpPostedFileBase获取byte []的方法

private static byte[] GetFileBytes(HttpPostedFileBase file)
{
    var streamLength = file.InputStream.Length;
    var imageBytes = new byte[streamLength];

    file.InputStream.Read(imageBytes, 0, imageBytes.Length);
    return imageBytes;
}

// MyOffersController

public ActionResult JobOfferReplies(int jobOfferId)
{
    List<ApplyForm> allReplies = dbConnection.ApplyForms.Where(x => x.TargetOfferId == jobOfferId).ToList();

    return View(allReplies);
}

// JobOfferReplies View

@model List<SourceTreeITMatchmaking.Core.Model.ApplyForm>

@{
    ViewBag.Title = "JobOfferReplies";
    Layout = "~/Views/Shared/_Layout.cshtml";
}
<div>
     @Html.ActionLink("Download CV", "DownloadCv", "MyOffers", new {file = applyForm.FileData, contentType = applyForm.ContentType }, new { @class = "btn btn-default pull-left" })
<div>

// MyOffersController

public FileContentResult DownloadCv(byte[] file, string contentType)
{
    return new FileContentResult(file, contentType);
}

Answer 1

在我们的代码中，我们按如下方式执行：

entityItem= new byte[file.ContentLength];
file.InputStream.Read(entityItem, 0, file.ContentLength);
file.InputStream.Close();

并返回

return File(entityItem, "application/octet-stream");

ASP.NET MVC从byte []返回文件

1 个答案: