Convert string to HttpPostedFileBase

Question

I am trying to do upload attachment functionality using MVC. My method that is actually doing the upload/save attachment is expecting a HttpPostedFileBase type.

public virtual string Upload(HttpPostedFileBase fileName) 
{
     //Code to upload/save attachment.
}

My problem is "fileName" is being passed from the UI as a string. How can I convert the string(file path name) into something my Upload method can work with.

Thanks in advance.

Solution 1

As mentioned by others, your form should look something like this:

<form id="form_UploadFile" action="" method="post" enctype="multipart/form-data">
  <label for="file">Filename:</label>
  <input type="file" name="file" id="file" />
</form>

Then as you mentioned you are trying to post via ajax, you can use jQuery serialize() to serialize the formData to be pushed to your controller.

$('#form_UploadFile').serialize();

Solution 2

You can't just pass a string from the UI, you need to upload the file from an input type="file".

Solution 3

you have to have your <form> tag to look like this:

<form action="" method="post" enctype="multipart/form-data">

Then you will receive proper HttpPostedFileBase object

You may refer to this article regarding all details.

UPDATE

Using ajax to submit form does not make any difference:

@using (Ajax.BeginForm("YourActionName", null, new AjaxOptions { UpdateTargetId = "YourTargetId" }, new { enctype = @"multipart/form-data" }))
{
    //Your inputs here
}

Solution 4

Did you remember to use the verbose Html.BeginForm method?

    @using (Html.BeginForm("Attach", "File", FormMethod.Post, new { enctype = "multipart/form-data" })) {
    }

The important part is enctype="multipart/form-data"

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