Question

I have a webpage that has 3 file inputs. There are specific fields on the form that needs to be sent when user uploads the file. I am not able to figure out how do i add custom data to my POST and how do i retrieve it back on the server. This is how my code looks like:

ASPX Page with 3 file inputs and other text boxes/dropdowns:

<form action="FilesUploader.ashx" method="post">

    <div id="dvNewAttachment1">
        <span>Attachment Type</span>
        <select id="ddlAttachmentType1">
            <option>T1</option>
            <option>T2</option>
            <option>T3</option>
        </select>
        <span>Description</span>
        <input id="txtDesc1" />
        <select id="ddlApproval1">
            <option>Yes</option>
            <option>No</option>
        </select>
        <input id="fileUploader1" type="file" runat="server" />
    </div>
    <br />
    ---------------
    <div id="dvNewAttachment2">
        <span>Attachment Type</span>
        <select id="ddlAttachmentType2">
            <option>T1</option>
            <option>T2</option>
            <option>T3</option>
        </select>
        <span>Description</span>
        <input id="txtDesc2" />
        <select id="ddlApproval2">
            <option>Yes</option>
            <option>No</option>
        </select>
        <input id="fileUploader2" type="file" runat="server" />
    </div>
    <br />
    -------------------------------
    <div id="dvNewAttachment3">
        <span>Attachment Type</span>
        <select id="ddlAttachmentType3">
            <option>T1</option>
            <option>T2</option>
            <option>T3</option>
        </select>
        <span>Description</span>
        <input id="txtDesc3" />
        <select id="ddlApproval3">
            <option>Yes</option>
            <option>No</option>
        </select>
        <input id="fileUploader3" type="file" runat="server" />
    </div>


<input type="submit" />

</form>

This is how my handler looks like:

public void ProcessRequest(HttpContext context)
        {

            HttpPostedFile myFile = context.Request.Files[0];

            int nFileLen = myFile.ContentLength;

            byte[] buffer = new byte[nFileLen];

            using (BinaryReader br = new BinaryReader(myFile.InputStream))
            {
                br.Read(buffer, 0, buffer.Length);
            }

        }

As you can see i have 3 uploads and each has Attachment Type and description associated with it which i need to retrieve for each input file in my handler.

Right now i am just processing file from the first input but later i am going to loop thru the inputs and process them.

Answer 1

If your handler do not receive files that you place in file uploaders then your form needs to have additional attribute like this:

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

In order to get values from dropdowns on server you need to provide a name attribute to them:

<select id="ddlApproval1" name="ddlApproval1">
    <option>Yes</option>
    <option>No</option>
</select>