Access SharePoint document or List item attachment from public site

Make the SharePoint document available to anonymous user without enabling anonymous access at web application level or site collection level.  If we enable anonymous access at top level then the content security will be lost.  But without enabling anonymous at top level we can make a document from document library or a list attachment to the public users using SharePoint list property.

SharePoint list has a property “AllowEveryoneViewItems”, which helps to make the document/list item attachment available to the public users.  This is the Boolean property. By setting this property to “TRUE” we can allow public user to access the document. But the public should access the direct document or list item attachment url because the public users will be able to navigate though SharePoint objects like document library or custom list.

Once the “AllowEveryoneViewItems” property set to “TRUE” then we can user the document url in any place over web for public access.

The property can be set in different ways using back end scripts or code but not through SharePoint UI.

1. Using Server Object Model

using (SPSite site = new SPSite("[site collection url]"))

{

using (SPWeb web = site.OpenWeb())

{

SPList list = rootWeb.Lists.TryGetList("[list title]");

if (list != null)

{

if (!list.AllowEveryoneViewItems)

{

list.AllowEveryoneViewItems = true;

list.Update();

}}}}

2. Using PowerShell Script

$web = Get-SPWeb -Identity "[site url]"

$list = $web.Lists.TryGetList("[list title]");

$list.AllowEveryoneViewItems = $true

$list.Update()

3. Using List Definition XML

Name="[list name]"

DisplayName="[list display name]"

Description="[list description]"

Type="10000"

BaseType="0"

Default="True"

VersioningEnabled="TRUE"

Hidden="FALSE"

AllowEveryoneViewItems="TRUE"

HiddenList="FALSE" />

It is important to note here that this property does not apply to all list items, but only to documents in document libraries or to attachments in list items. So you have to access this file directly for it to work ! (reference: SPList.AllowEveryoneViewItems property)

Here is the code snippet for accessing the file directly using HttpWebRequest

var fileContent = String.Empty;

//construct path to the navigation file

string fileUrl = "[full url of the file]";

//create webrequest to fetch this file!

var httpRequest = (HttpWebRequest)WebRequest.Create(fileUrl);

using (var webResponse = (HttpWebResponse)httpRequest.GetResponse())

{

if (webResponse.StatusCode == HttpStatusCode.OK)

{

using (var responseStream = new StreamReader(webResponse.GetResponseStream()))

{

//if we get the response, read the content from file as string

fileContent = responseStream.ReadToEnd();

}

}

}