coding

SharePoint Login as a Different User

What the hell Microsoft? Why did you decide to remove the ability for a user to logon as a different user in SharePoint 2013? It was there in 2010, but this feature is not there in 2013.

Microsoft's recommendation is to right-click on Internet Explorer and then select run-as and then enter your username and password. This is not a good option for most users and in our environment it is not practical. So to get this functionality back, we will create a SharePoint feature that is deployed at the farm level. There are some sites out there that detail this but there is one problem with all of them, they do not redirect the user back to the same site where they did the logout / login function. I have included the specific code to solve the problem but I am not including the details on how to create the feature. Once the feature is created add an empty element to the project and paste in the code below. The LogoffAndLogin() javascript function will get the current subsite and pass it in as a parameter to then allow the logoff webservice to redirect the user back to the original page after login.

  1. <?xml version="1.0" encoding="utf-8"?>
  2. <Elements xmlns="http://schemas.microsoft.com/sharepoint/">
  3. <CustomAction
  4. Id="LoginScript"
  5. ScriptBlock="function LogoffAndLogin(){ if (typeof SP != 'undefined') { var siteCollUrl = '';SP.SOD.executeFunc('SP.js', 'SP.ClientContext', function(){var clientContext = new SP.ClientContext.get_current();var site = clientContext.get_site();clientContext.load(site);clientContext.executeQueryAsync(Function.createDelegate(this, function(){siteCollUrl = site.get_url();var fullURL = siteCollUrl + '/_layouts/closeConnection.aspx?loginasanotheruser=true&amp;amp;Source=' + siteCollUrl; window.location = fullURL;}))})} else { alert('An error occurred during the logoff process, please try again.');}};"
  6. Location="ScriptLink">
  7. </CustomAction>
  8. <CustomAction
  9. Id="LogInAsUser"
  10. GroupId="PersonalActions"
  11. Location="Microsoft.SharePoint.StandardMenu"
  12. Sequence="998"
  13. Title="Sign in as a Different User"
  14. Description="Sign Out and Login as a Different User">
  15. <UrlAction Url="javascript:LogoffAndLogin();"/>
  16. </CustomAction>
  17. </Elements>

I have the code all in one line and I realize that it might be a bit difficult to follow. I have included the code broken out as multiple lines to help you follow what is going on.

  1. LogoffAndLogin(){
  2. if (typeof SP != 'undefined') {
  3. var siteCollUrl = '';
  4. SP.SOD.executeFunc('SP.js', 'SP.ClientContext', function(){
  5. var clientContext = new SP.ClientContext.get_current();
  6. var site = clientContext.get_site();
  7. clientContext.load(site);
  8. clientContext.executeQueryAsync(Function.createDelegate(this, function(){
  9. siteCollUrl = site.get_url();
  10. var fullURL = siteCollUrl + '/_layouts/closeConnection.aspx?loginasanotheruser=true&amp;amp;Source=' + siteCollUrl;
  11. window.location = fullURL;
  12. }))
  13. })
  14. }
  15. else {
  16. alert('An error occurred during the logoff process, please try again.');
  17. }
  18. };

This has worked well in our environment. This is a stupid problem that MS created, but this solution should work well to solve it. Good luck !!



SharePoint security trimmed site list

Okay, so it has been a bit since I have posted anything, mainly due to that I have not anything notable to post.  This is not due to me not doing anything notable but that the things that I have done that were notable were proprietary and I did not feel comfortable disclosing in a public forum. 

So the problem that I was given was that when people landed on the root site within the root site collection of our managed path / application the user hit a page that was essentially blank.  From there they did not know where they should go and did not really know what they would be able to access.  So here comes a webpart that can help solve the problem.  What the goal of this webpart was is to create a security trimmed list of sites the user would have access at the root level.  I am not going to go through each and every step for creating a webpart but I will give some high level info since these are steps that I struggled with when creating the webpart.

 

  1. So first off, when you are creating this webpart select the "Visual Web Part option" in the project type.
  2. You MUST select DEPLOY AS FARM SOLUTION.  The sandboxed solution will not have access to the necessary objects needed for this webpart.  Specifically getting all site collections in a web application (managed path).
  3. To start we will create two classes.  SiteLookup and SPSiteInfo. 

    SiteLookup

    1. using Microsoft.SharePoint;
    2. using System;
    3. using System.Collections.Generic;
    4. using System.Linq;
    5. using System.Text;
    6. using System.Threading.Tasks;
    7.  
    8. namespace SPSiteListing.ListSPSites
    9. {
    10. class SiteLookup
    11. {
    12. private Boolean _EnableTrimming;
    13. private SPContext _Context;
    14. private string _CurrentUserName;
    15. public SiteLookup(SPContext context, Boolean enablePermissionTrimming)
    16. {
    17. _EnableTrimming = enablePermissionTrimming;
    18. _Context = context;
    19. _CurrentUserName = context.Web.CurrentUser.LoginName;
    20. }
    21. public List<SPSiteInfo> GetSites()
    22. {
    23. if (IsRootInApplication())
    24. {
    25. var list = new List<SPSiteInfo>();
    26. list.AddRange(GetSitesUnderCurrentWeb());
    27. list.AddRange(GetSitesUnderManagedPath());
    28. return list;
    29. }
    30. else
    31. return GetSitesUnderCurrentWeb();
    32. }
    33. public Boolean IsRootInApplication()
    34. {
    35. if (_Context.Site.RootWeb.Url != _Context.Site.Url)
    36. return false;
    37. if (_Context.Site.WebApplication.Sites[0].Url != _Context.Site.Url)
    38. return false;
    39. return true;
    40. }
    41. public List<SPSiteInfo> GetSitesUnderManagedPath()
    42. {
    43. var sites = new List<SPSiteInfo>();
    44. var applicationSites = _Context.Site.WebApplication.Sites;
    45. foreach (SPSite item in applicationSites)
    46. {
    47. //you must set disable catching access exceptions to prevent sharepoint from catching it
    48. item.CatchAccessDeniedException = false;
    49. try
    50. {
    51. if (item.RootWeb.DoesUserHavePermissions(_CurrentUserName, SPBasePermissions.Open) || !_EnableTrimming)
    52. sites.Add(new SPSiteInfo(item));
    53. }
    54. catch (UnauthorizedAccessException)
    55. {
    56. //The user does not have access to check their access. So an exception will be thrown.
    57. //This will not cause a problem to not do anything with it, since we are security trimming
    58. //we do not want this one listed anyway.
    59. }
    60. }
    61. return sites;
    62. }
    63. public List<SPSiteInfo> GetSitesUnderCurrentWeb()
    64. {
    65. var sites = new List<SPSiteInfo>();
    66. if (_EnableTrimming)
    67. {
    68. foreach (SPWeb item in _Context.Web.GetSubwebsForCurrentUser())
    69. {
    70. sites.Add(new SPSiteInfo(item));
    71. }
    72. }
    73. else
    74. {
    75. foreach (SPWeb item in _Context.Site.AllWebs)
    76. {
    77. sites.Add(new SPSiteInfo(item));
    78. }
    79. }
    80. return sites;
    81. }
    82. }
    83. }

    SPSiteInfo

    1. using Microsoft.SharePoint;
    2. using System;
    3. using System.Collections.Generic;
    4. using System.Linq;
    5. using System.Text;
    6. using System.Threading.Tasks;
    7.  
    8. namespace SPSiteListing.ListSPSites
    9. {
    10. class SPSiteInfo
    11. {
    12. public string SiteName { get; private set; }
    13. public string SiteUrl { get; private set; }
    14. public string HTMLLink
    15. {
    16. get
    17. {
    18. return String.Format(@"<a href=""{0}"">{1}</a>",
    19. SiteUrl,
    20. String.IsNullOrEmpty(SiteName) ? SiteUrl : SiteName);
    21. }
    22. }
    23. public SPSiteInfo(SPSite site)
    24. {
    25. try
    26. {
    27. SiteName = site.RootWeb.Title;
    28. }
    29. catch (UnauthorizedAccessException)
    30. {
    31. //since the user does not have access to get the title, we can do something
    32. //here if we want with demonstrating that. but it isn't necessary
    33. }
    34. SiteUrl = site.Url;
    35. }
    36. public SPSiteInfo(SPWeb site)
    37. {
    38. SiteName = site.Name;
    39. SiteUrl = site.Url;
    40. }
    41. }
    42. }
  4. So now that we have the classes written to get the data, we need a something to display the data in the webpart. To do that we will use the ascx file created already (just adding a ul with an id and a runat) and add some code in the page_load method.

    ASCX file

    1. <ul id="siteList" runat="server">
    2.  
    3. </ul>

    ASCX code behind

    1. protected void Page_Load(object sender, EventArgs e)
    2. {
    3. SiteLookup query = new SiteLookup(SPContext.Current, true);
    4. foreach (var item in query.GetSites())
    5. {
    6. var li = new HtmlGenericControl("li");
    7. li.InnerHtml = item.HTMLLink;
    8. siteList.Controls.Add(li);
    9. }
    10. }


So that is basically it. There are some details that are not covered in this post, but this should get you past the things that I struggled with when I created my webpart.


Good Luck !!

The benefits of Early Returns

Returning early in a method is something that we have debated quite a bit at work, and what I see is that there reasons to return early and times to have a single return.  There are two reasons to return early one which prevents code from executing when it does not need to execute and the other is to make code more readable.  As for having a single return the main reason is for code readability but from a different aspect than returning early.

So to demonstrate the point I have included the same method written with return early and on with a single return here.

In this comparison I have simple code that is checking if a SMTP mail message is valid.  I am checking that the message is not null, there is at least one From address, one To address, and something in the body.  This might be a bit of an extreme example but it does work to illustrate the point that early returns can make the code more readable.  With regard to efficiency the early returns make the code more efficient in that there is no need to continue execution if one of the early message checks fail.  Using this example, if the From address is not valid (not containing an @ symbol) then the code will return a false immediately rather than continue checking running the code.

Something to note with this comparison, the method using the early returns has a total of 27 lines whereas the method using the single return has 46 lines.  So unless you are being paid by the line of code when writing methods such as this, it is better to have early returns.

One additional note, if you code looks like this….

you need to do something else because this is just bad (I was emailed this code and I am not sure of its original source).

What is the point of out of the box SharePoint?

SharePoint is a powerful platform, but is SharePoint really anything without custom coding and is an out of the box solution worth the trouble?  The short answer is if you want a web based file share out of the box is fine…but if you need anything else, then plan on coding and jumping through a few hoops.

So what do you get out of the box?

  • File sharing

  • Basic (very basic) versioning control

  • Change the background and the color

So when does coding being?  It begins when you want to change the “SharePoint” word or logo at the top left of the screen.  When it comes to SharePoint the thought of it as a CMS needs to go away and it needs to be thought of as a platform for development. 

SharePoint demonstrates its extensibility and need for custom development when it comes to utilizing functionality that is promised in the out of the box functionality but is not delivered.  One area that this is very apparent is with version control and retention policies.  Version control works well out of the box but it does not do anything with retention policies meaning that if you need to maintain the current version’s retention policy independent from the historical version’s retention policy custom code will be needed.

To accomplish this functionality there are five requirements.

  1. A document library to hold the current documents.

  2. A content type that can be used for the record with applicable metadata.

  3. A record center with a record library to capture the versions.

  4. The record center must be setup as a Send To location for the SharePoint farm.

  5. Some code with an event receiver to capture the versions.

Using this methodology when a user begins the process to update a document the current version is immediately sent to the event receiver and based on the logic within there is a determination whether or not to archive.  The document is then sent to Send To location (the record center) which will handle the routing to the correct record library.  The record library can have whatever retention policies required by the documents applied.

Functionally there is only a few lines of code that are required for this to function:

  1. public override void ItemUpdating(SPItemEventProperties properties)
  2. {
  3. SPFile file = properties.ListItem.File;
  4. string strOut = "";
  5. OfficialFileResult retVal = file.SendToOfficialFile(out strOut);
  6. string value = retVal.ToString();
  7. }

However there is a bit more code that is required to make this a fully functioning option.  Click Here to see the full code (not including the installer for the feature).