Installer projects in Visual Studio are for creating the Setup.exe and the MSI for installing the other projects in a solution. However, I discovered an oddity that caused havoc with our source control system. Continue reading “Visual Studio Installer Projects and SVN”
Author: Andy Burns
Handling Errors when doing file IO
I came across a pattern in .NET that I’d not thought of before. The scenario is, I’m reading from a file and deserializing it’s contents (a List of ‘Foo’ objects). Exceptions can be thrown at two points:
- When I’m reading the file
- When I’m deserialising the xml
Obviously, I want to make sure that the file handle is released if the deserialisation fails. However, I can’t deal with that in a single try block, as if the exception is in the file IO, then the file handle won’t exist to close in a finally block! Continue reading “Handling Errors when doing file IO”
.NET Framework versions, language versions, and CLR versions – all a bit fraught…
The .NET framework is a bit confusing until you get your head round the components of it, and the way that Microsoft name things.
.NET has a thing called the common language runtime (CLR). (This is the .NET equivalent of the Java Runtime). Different versions are essentially different VMs, and can coexist. The CLR runs code that is an Intermediate Language (IL) (aka the Common Intermediate Language (CIL)). Whatever code you write in C# or VB.NET actually only gets partially compiled into IL code. It’s a lot like Java Bytecode.
The Base Classes are the library of DLLs for the framework (and are sometimes incorrectly referred to as the framework). Think of it as Win32 for .NET. These constitute the .NET API – and have different versions too. A different version of the base classes, though, does not mean a different CLR – for example, frameworks version 2, 3 and 3.5 all use the same CLR, but present a different external API and have different language features. Indeed, the base classes of framework version 3.5 are a superset of version 3, which are a superset of 2. This means framework 2 code will run on machines with the 3.5 installed.
The languages have different versions too, and this is where things start to get confusing. The different language versions have different compilers, which emit backward compatible IL. This is to be expected since there is no new version of the CLR. In plain terms this means that all the new language features can be used with older projects. E.g. C# 3.0 code can run on the .NET 2 Framework, provided you haven’t used any of the libraries that are part of a later framework. The C# 3.0 code will be partially compiled into the same version of IL code as your C# 2.0 code, so the only problems come if you are using libraries that aren’t part of that .NET Framework.
(Note to self – must remember – C# version is independent of Framework version)
So why would you want to use C# 3.0 over C# 2.0? Well, the language adds a number of new features too – such as automatic properties, relaxed delegates, object initialisers, type inference, anonymous types, extension methods, lambdas and partial methods.
Hopefully this chart might explain things a bit. I’m pretty sure it’s right, although I’m recreating it from memory and can’t entirely remember…
|
|
Framework Version 1.1 |
Framework Version 2.0 |
Framework Version 3 |
Framework Version 3.5 |
|
CLR |
1.1 |
2.0 |
2.0 |
2.0 |
|
Library versions |
1.1 |
2.0 |
3.0 (including 2.0 sp1) |
3.5 (including 2.0 sp1 & 3.0 sp1) |
Similar chart here:
http://www.leonmeijer.nl/archive/2007/06/11/50.aspx
…though the Microsoft guy who presented to me didn’t say anything about a CLR 3.0. I suppose there may be one which is backwardly compatibile?
Changing the SmallSearchInputBox delegate control
A colleague of mine was wanting to make some changes to the SmallSearchInputBox delegate control in SharePoint 2007. That’s the control that appears on most pages, looking like:
This control is a ‘Delegate control’ – that is, you can create features to override the currently used control. What my colleague wanted to do was not display the ‘Scope’ drop down list, the Advanced Search link, and to include prompt text (something like ‘Enter Search…’). A quick dig into the FEATURES folder in 12 Hive showed that the control had a number of properties.
(The features that this information applies to are the OSearchBasicFeature and OSearchEnhancedFeature. Both contain files called ‘SearchArea.xml’, and that contains the code below. I found the folders with this in:
%12 Hive%TemplateFeaturesOSearchBasicFeature
%12 Hive%TemplateFeaturesOSearchEnhancedFeature )
<?xml version="1.0" encoding="utf-8" ?>
<Elements xmlns="http://schemas.microsoft.com/sharepoint/">
<Control
Id="SmallSearchInputBox"
Sequence="25"
ControlClass="Microsoft.SharePoint.Portal.WebControls.SearchBoxEx" ControlAssembly="Microsoft.SharePoint.Portal, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c">
<Property Name="GoImageUrl">/_layouts/images/gosearch.gif</Property>
<Property Name="GoImageUrlRTL">/_layouts/images/goRTL.gif</Property>
<Property Name="GoImageActiveUrl">/_layouts/images/gosearch.gif</Property>
<Property Name="GoImageActiveUrlRTL">/_layouts/images/goRTL.gif</Property>
<Property Name="UseSiteDefaults">true</Property>
<Property Name="FrameType">None</Property>
<Property Name="ShowAdvancedSearch">true</Property>
</Control>
</Elements>
This shows a property ShowAdvancedSearch which sounded pretty promising for turning off the Advanced Search link. We decided to see what other properties were available, and found a good article by Clint Cherry about the SmallSearchInputBox control, and the MSDN docs. The Property tags in the XML for the delegate control set the properties of the web control class – e.g. GoImageUrl matches the GoImageUrl property on the class. Much to our pleasure, we found the QueryPromptString displays text in the search control which vanishes when it receives focus, and the DropDownMode property allows us to turn off the scope dropdown list. Hurrah!
For the values that you can set the drop down mode to, see the MSDN docs again
Why SharePoint Records Management will struggle…
I recently got a lot of my old APS photos scanned, and I’ve been working my way through them all, trying to sort them out and arrange them. I’ve been doing this by, well, putting them in folders such as ‘2003-06 – French Alps Kayaking’. At the same time, though, I wanted to give my friends copies of the photo’s which they were in, and I did this by, well, creating another folder for each of them, and copying pictures into them too. Not dreadfully sophisticated.
A couple of my friends asked why I didn’t just use some albuming application, or something like Flickr, and tag the images. That way, I could browse by multiple criteria. And I’ve gotta say, it would be neat. However, I want to be able to look at these photos when I’m an old man. I mean, my grandfather was showing me pictures of when he was a kid – so that’s about 75 years ago. Does anyone consider 75 year survival times for digital media? Nope. But I suspect that file systems and JPEGs, even if they aren’t still in use, will be easier to migrate. Flickr? Well, obviously, no website has ‘Established 1932’ on it. I’m not sure I’d trust something like that to still be around. Other tagging and abluming products – again, I’m not convinced. I decided I’d stick with just folders.
This set me thinking about Record Management, and taxonomy vs tagging. Continue reading “Why SharePoint Records Management will struggle…”
Setting up an Email Server
A short, useful article about setting a machine up as a mail server – this proved useful when I was setting up a machine for a demo recently. I must confess, I’ve never set up a mail server before, but it was quite simple, apart from the problems I had with finding the right Windows Server installation disc.
Uploading Files to SharePoint using the Web Services
Thankfully, someone seems to have looked at other ways of uploading files via the web services – this time using a direct PUT command. That is an approach which is a little odd, to be honest, and I suppose not really Web Services so much as plain old web-server. Still, I’m going to have a look at this approach – and it’d be great if it works.
DateTimePicker – no BackColor property, not nullable
More Windows forms stuff. I don’t like really complex Web forms controls ‘cos sometimes they seem a bit flakey – but I’m beginning to wonder if Windows Forms stuff is any better.
Two problems with the DateTimePicker. First, it can’t have a null value. What? You might not want to have a value in it? That’s craaazzzy! Inconceivable! What do you mean that your database tables allow null values in a DateTime column?
All you can do is set ShowCheckbox to ‘true’. This will give you a little checkbox, to turn on or off the editing of the value. You could then wrap the DateTimePicker, and return yourself null if the ‘Checked’ value is false.
Secondly, it has no BackColor property, so I couldn’t colour it pink when the field was invalid, meaning it had to have a value – therefore, the checkbox mentioned above has to be ‘Checked’. I managed to get around this by subclassing the DateTimePicker – but had some problems when you then focussed on it to try to edit it. My solution (below) was to turn off any background colour during editing…
Continue reading “DateTimePicker – no BackColor property, not nullable”
TableLayoutPanel – doesn't autosize or autoscroll correctly
I’ve been doing some Windows forms programming lately – not really my thing, but needs must. I’ve got an application which needs to dynamically create a form at run time, and so I’m using a System.Windows.Forms.TableLayoutPanel.
All the controls contained by the TableLayoutPanel resize automatically, and the TableLayoutPanel automatically provides scrollbars. “Great!”, I thought, “This will deal with large forms nicely.” Wrong!
The problem is when form has too many fields – it becomes deeper than the display area of the TableLayoutPanel. This is fine – the TableLayoutPanel should automatically add a vertical scrollbar, and adjust the size of the controls it contains to fit in the smaller area. Except it doesn’t. What I actually get is this:
Notice that I’ve got a vertical scrollbar, but it hasn’t resized the child components. This, they overlap some of the fields – and I now have a nice horizontal scrollbar. Arse.
I eventually found that others had had this problem and told Microsoft about it. However, they’ve decided not to fix it. Thanks Microsoft, that cost me an hour and half – it’d be wise to fix it. I found the answer from the same link – add a vertical scrollbar’s width as padding on the right of the TableLayoutPanel.
The circular logic of the WSS Lists Webservice GetListContentTypes call
So, I need to get a list of the content types applied to a library. The Lists webservice has a call for this:
<getlistcontenttypes xmlns="http://schemas.microsoft.com/sharepoint/soap/">
<listname>string</listname>
<contenttypeid>string</contenttypeid>
</getlistcontenttypes>
So, I’m connected to a site, I supply a list name to identify the list… …but what do I give as a contentTypeId? I don’t have a f$%king clue – I was calling this function to try to find out what content types were valid!
Well, good news. It doesn’t seem to matter what you put in, you always get a list of all the content types on the list. I used the following code…
WS_Lists.Lists lsts = new WS_TestApp.WS_Lists.Lists();
lsts.Credentials = System.Net.CredentialCache.DefaultCredentials;
XmlNode node = lsts.GetListContentTypes(libraryName, contentTypeID);
I figured that maybe they wanted the base content type for what I wanted back, so I tried setting contentTypeID to documents (0x0101) and got back a list of all the content types. I then set contentTypeID to “fish”, and still got back a list of all the content types. As far as I can tell, the second parameter doesn’t do anything.
Side note: The first content type returned is your default content type.
Side note 2: There doesn’t seem to be an easy way of identifying non-visible content types…
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