Stefan Costan

The Crisis of Credit Visualized by Jonathan Jarvis

2009-02-25T10:01:00.006+02:00

The Crisis of Credit Visualized from Jonathan Jarvis on Vimeo.

How to use ASP.NET Caching with IconSet

2009-02-05T09:45:00.009+02:00

I usually get questions regarding the performance of the IconSet field (http://www.codeplex.com/iconset) and I know there are some issues when there is more than one field in the view.

Using simple ASP.NET caching techniques the overall performance of the custom calculation can be improved. On the other hand the ASP.NET caching has some drawbacks for this scenario:

1. If the cache did not expire you will always see in views the cached value of the field and not the current one.
2. With this approach is no way to clear the cache for an item when the item gets updated.

How can we improve the overall effect disregarding the above drawbacks?

The page that always gets called in views is “~\web server extensions\12\TEMPLATE\LAYOUTS\csc.SharePoint\CustomFields\IconSetField\IconSetDisplay.aspx”.

This page can be modified without the need to recompile the entire application.

Let’s proceed:

The query string parameters passed to the page are:

StaticName – the static name of the IconSet field
ListID – the GUID of the current list
ItemID – the ID (int) of the list item
Value - the calculated value

First improvement technique is to use “VaryByParam” attribute of the OutputCache directive.

<%@ OutputCache Duration="15" VaryByParam=" ItemId" %>

If you have more than one IconSet field into your view you might want to regenerate the page if the “StaticName” changes, so your OutputCache directive becomes:

<%@ OutputCache Duration="15" VaryByParam=" StaticName;ItemId" %>

As general conclusion for the above modification: Use them as far as the values of the calculation are not changing within the cache time frame set in “Duration” attribute, or the outline drawbacks are somehow acceptable in your scenario. Nevertheless you can get some inspiration from Jørn Bratland's post.

If you want to find more about ASP.NET caching please refer to this article

Running Ajax within SharePoint List Views columns

2009-01-10T13:07:00.019+02:00

I was google-ing for days over the net to find a way of running Ajax within SharePoint list views columns with minimum of fuss, unfortunately with no success. The goal was to run some custom action on the server based on the column value and to return to the client a small image that represents the visual representation of the column value (see http://www.codeplex.com/iconset ), the image being displayed within the list view.

I have decided to do it in my own way. So let’s proceed.

First thing was to modify the field Display Render Pattern as following:

Include a image HTML tag that shows a loader image that will be changed by the Ajax code.
Include a script HTML tag that will hold on a external file the AJAX code.

A bit of explanation is need. The attribute “url” is used by the AJAX script “xmlHttp.js” to get the data from the server. First the script should hook on the window “OnLoad” event. Using the function “addLoadEvent” all column images from our current list view will be attached to an AJAX object that will handle the processing on the server. The passed parameters to the AJAX object are the processing “url” and the ID of the image object. The ID is passed in order to change the image source when a new image will be available.

The AJAX script:

The “stateChanged” function gets the raw data as string from the processing ASPX page and set’s the image alternateText and src properties of object with the given ID.

The ASPX page does not have any special or tricky code into it. Basically it should be able to return to the client a simple string like: client_data1##client_data2, where “client_data1” is the URL of the new image and “client_data2” is the alternate text.

So the code for “getImage.aspx” should be similar with the bellow sample:

The above code I did not tested, but is a modified version of an existing project that works very well.

The result should be similar as within bellow screenshot:

Using IconSet SharePoint custom field with Ciloci library embeded functions

2008-11-08T11:10:00.012+02:00

So, let’s start.

Date & Time Functions

1. Calculate the difference of two dates:

=DAYS360(DATEVALUE("[Date_Field_1]"), DATEVALUE("[Date_Field_2]"))

2. Calculate the difference between a date and today:

=DAYS360(DATEVALUE("[Date_Field_1]"), TODAY())

Logical Functions

1. Using AND, OR, IF statements

=IF(OR("[Date_x0020_finished]"="","[Date_Field_1]"="","[Date_Field_2]"=""),0,days360(datevalue("[Date_Field_3]"),datevalue("[Date_Field_1]")) / days360(datevalue("[Date_Field_1]"),datevalue("[Date_Field_2]")))

In the example above you can use AND instead of OR. The above formula returns 0 if any of the date fields are empty or the result of a more complex calculation.

2. Using checks with SharePoint “Multiple lines of text” field

=IF(AND(“[Status]”="completed", OR(“[Multiple_lines_of_ text_Field_1]” =""<div">"</div">", “[Multiple_lines_of_ text_Field_1]” = "<div"> "</div">")), 0,1)

The formula returns 0 if the choice field Status is “completed” and the Multiple_lines_of_ text_Field_1 is empty, 1 otherwise. A Multiple_lines_of_ text_Field_1 is empty when is equal with <div></div> or <div> </div>.

This article is a living post that will grow in time, with answers to your questions.

Using IconSet SharePoint custom field with "yes/no" fields

2008-11-04T10:32:00.000+02:00

I’m getting question on how can I calculate this and that formula, using the IconSet custom field. I decided to post for every single question a very short article on how you can use it in real life.

I think an image is more than a 1000 words, so let’s start…

This example will show a green and red icon only. The current version of the IconSet doesn’t have a template with 2 icons, so use this hack to go around.

SharePoint Custom Calculated Field: IconSet

2008-10-31T12:52:00.000+02:00

I was looking for some time for a SharePoint (MOSS,WSS) custom calculated field over the net for an internal project at work. After reading lots of posts and technical documentation on MSDN, I decided to create my own custom field to suit my needs.

The project is published on CodePlex (http://www.codeplex.com/iconset) with full description and source code.

I decided to share the project with the world, the only scope being the need to get feedback for future improvements.

I hope this piece of information will help people that are looking for similar functionality.

Short Project Description

The IconSet custom field is a combination between a Calculated field and the “Conditional Formatting” found on Microsoft Excel 2007 application. The user can define a mathematical formula and the rendering template for calculated value. It is a handy feature for all users that are using SharePoint on daily basis to use this custom field as a simple way of identifying visually, critical items within their lists.

Please check the project site regularly for updates. http://www.codeplex.com/iconset