add custom data to POST - asp.net

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>