\nThe Visual Basic Language on Silverlight<\/font><\/h2>\n<\/h2>\nPrior to the announcement of Silverlight 1.1<\/a>, Silverlight plug-ins were written in XAML and Javascript. While the Javascript model is certainly powerful, using VB is always my preference\u2014it\u2019s a language I know well, and its flexibility suits my programming style. Not to mention that the introduction of VB.NET into the Silverlight world brings with it many of the .NET Framework\u2019s types and APIs I\u2019ve come to rely on.<\/p>\nIf you\u2019ve had a chance to download the Silverlight 1.1 runtime<\/a>, you may have noticed that it\u2019s MUCH smaller than the full .NET Framework at 4.2 MB (and hopefully shrinking!). Clearly, some things have been factored out of the .NET Framework to keep the download size down and installation time short. And although a lot has been removed, the core set of types is included along with some APIs that are particularly useful for writing plug-ins\u2014things like a \u201clite\u201d version of System.Xml.dll, support for making web service calls, and so on. When deciding what aspects of the Visual Basic language and runtime should be included with Silverlight v1.1, we tried to follow a similar pattern: we wanted to preserve the core VB programming experience\u2014late binding, conversions, Linq, and so on; and we didn\u2019t want to bloat the download size with anything that wasn\u2019t absolutely necessary or didn\u2019t make sense in Silverlight\u2014things like some of the COM helpers (COM is not supported in Silverlight), financial functions, etc. It was a delicate balance to strike between functionality and overall size. The Silverlight 1.1 Alpha is our first crack at it\u2026 and it may be refined over the coming months with feedback. Here\u2019s a laundry list of what\u2019s supported\/not supported currently. (If you\u2019re interested in digging into the details, you can also view the types in the Object Browser using the tools described below.)<\/p>\nSupported\u2026<\/i><\/b> <\/h4>\n\n- Late Binding<\/b>: One of the most definitive features of the VB language, I find late binding to be especially useful in writing Silverlight code-behind.\n
- Conversions<\/b>: Implicit and explicit conversion operators are available\u2014Ctype, CStr, etc.\n
- Linq<\/b>: Currently, Linq over objects is supported\n
- String utilities<\/b>: Len(), InStr(), Mid(), UCase(), etc\n
- VB Collection<\/b>: Most folks either love it or hate it. A subset of generic collections is also supported. (Non-generic collections are considered obsolete for Silverlight.)\n
\n- Dictionary(Of Key, Value)<\/b>\n
- List(Of T)<\/b>\n
- ArrayList (Obsolete)<\/b>\n
- BitArray (Obsolete)<\/b>\n
- Hashtable (Obsolete)<\/b>\n
- Queue (Obsolete)<\/b>\n
- SortedList (Obsolete)<\/b>\n
- Stack (Obsolete)<\/b><\/li>\n<\/ul>\n
- Math utilities<\/b>: Rnd(), Random()\n
- IIF()<\/b>\n
- Information utilities<\/b>: Things like IsNumeric(), IsDate(), UBound(), LBound(), and so on\n
- Date utilities: <\/b>Now(), TimeOfDay(), Year(), etc\n
- Constants:<\/b> vbCrLf, vbTab, etc. Some of the more obscure constants have been removed, but the core set is included.\n
- All core VB Language Constructs: <\/b>Type Inference, anonymous delegates, Handles, etc<\/b><\/li>\n<\/ul>\n
Not Currently Supported\u2026<\/i><\/b> <\/h4>\n\n- The My Namespace:<\/b> We removed this for Alpha release because much of the existing My Namespace doesn\u2019t make a ton of sense in Silverlight. <\/b>\n
- XML Literals: <\/b>The compiler support for XML literals is present, but System.Xml.Linq (which the feature depends on) is not available in Silverlight 1.1. <\/b>\n
- COM Support: <\/b>Silverlight plug-ins are not allowed to call COM components, so we removed the VB utilities related to COM (e.g., the COM Class attribute)<\/b>\n
- FileSystem Object (VB6 Compatibility): <\/b>Direct access to the file system is not permitted, so these APIs were removed. Alternatively, you might check out System.IO.IsolatedStorage if you need to persist data locally<\/b><\/li>\n<\/ul>\n
As a sort of test piece, I recently took a look at the Clock Sample<\/a> and wanted to see if the feature set we settled on enabled me to write VB code as I normally would for a Windows Forms or WPF application. The code basically just sets the minute, second, and hour hands on the clock to the current time (approximately). Here\u2019s what it looks like\u2026<\/p>\n\n‘ Anonymous delegates, Handles–isn’t it pretty?<\/span><\/p>\n<\/span>Public<\/span> Sub<\/span> Canvas_Loaded() Handles<\/span> Me<\/span>.Loaded<\/span><\/p>\n <\/span>InitializeComponent()<\/span><\/p>\n <\/span>‘ Type inference; DateTime functions<\/span><\/span><\/p>\n <\/span>Dim<\/span> currentTime = Now<\/span><\/p>\n <\/span>‘ Conversions, type inference<\/span><\/span><\/p>\n <\/span>Dim<\/span> hourAngle = ((currentTime.Hour \/ 12) * 360 + currentTime.Minute \/ 2) + 180<\/span><\/p>\n <\/span>Dim<\/span> minAngle = ((currentTime.Minute \/ 60) * 360) + 180<\/span><\/p>\n <\/span>Dim<\/span> secAngle = ((currentTime.Second \/ 60) * 360) + 180<\/span><\/p>\n <\/span>‘ hourAnimation is a generated variable that makes use of WithEvents and Conversions<\/span><\/span><\/p>\n <\/span>‘ <\/span>Protected WithEvents hourAnimation As DoubleAnimation<\/span><\/span><\/p>\n <\/span>‘ <\/span>Me.hourAnimation = CType(Me.FindName(“hourAnimation”),DoubleAnimation)<\/span><\/span><\/p>\n <\/span>hourAnimation.From = hourAngle<\/span><\/p>\n <\/span>hourAnimation.To = hourAngle + 360<\/span><\/p>\n <\/span>minuteAnimation.From = minAngle<\/span><\/p>\n <\/span>minuteAnimation.To = minAngle + 360<\/span><\/p>\n <\/span>secondAnimation.From = secAngle<\/span><\/p>\n <\/span>secondAnimation.To = secAngle + 360<\/span><\/p>\nEnd<\/span> Sub<\/span><\/span><\/p>\n<\/blockquote>\nAll in all, this particular example looks and feels pretty VB to me\u2014which isn\u2019t to say we\u2019ve nailed it by any means\u2026 but the example does give some indication as to the type of VB experience we\u2019re striving for with Silverlight. Let us know what you think.<\/p>\n
\nTools for building Silverlight Plug-ins with VB<\/font><\/h2>\n<\/h2>\nUnless you\u2019re really into notepad , download the tools for Silverlight. The VS project templates alone are worth the bandwidth required, as they\u2019ll get you started in the right direction. In addition, many of the more interesting things you can do with Silverlight (e.g., animations, embedding videos, etc) are pretty tedious to wire-up by hand in XAML; using Expression Blend makes the process *much*<\/i><\/b> easier. All of the components mentioned below are available at: http:\/\/silverlight.net\/GetStarted\/<\/a>. I\u2019ve just included them here for convenience.<\/p>\n\nWhat to download<\/font><\/h2>\n<\/h3>\n\n- Silverlight 1.1 Runtime<\/b>: <\/a>This is the version of Silverlight that enables you to write VB code-behind. It includes a version of the factored .NET Framework, including the VB runtime (Microsoft.VisualBasic.dll).\n
- ASP.NET Futures Runtime<\/b>: <\/a>Among other features, the controls included in this download make it much easier to embed Silverlight controls and rich media in existing ASP.NET web applications\n
- VS Orcas Beta 1<\/b>:<\/a> Note: <\/i><\/b>You need to have the official Orcas Beta 1!<\/u><\/i> Earlier CTPs won\u2019t cut it. Even if you choose not to use Visual Studio to do your development, you\u2019ll need the Beta 1 VB 9.0 compiler, as it includes some changes required to target the slimmed-down .NET Framework.\n
- VS Add-On for Silverlight:<\/b><\/a> This component provides some project templates and IDE changes for building Silverlight applications in VB (and C#).\n
- Expression Blend 1.1 CTP<\/b><\/a>: The VS Add-On mentioned above does not include a designer for Silverlight; editing XAML is done in the XML editor. While the XML editor does support IntelliSense, I find it much easier to perform the visual and story board layouts in Expression Blend. (See the note below for the workaround required to use VB & Blend.)\n
- Silverlight SDK<\/b>:<\/a> The most interesting content in the SDK is the reference documentation for the VB runtime. It basically details what functions and types in Microsoft.VisualBasic.dll. The download also includes samples, although I generally prefer to see them online here: http:\/\/silverlight.net\/quickstarts\/managed.aspx<\/a>.<\/li>\n<\/ul>\n
If you run into any problems getting this stuff installed, please post the problem at the forums, http:\/\/silverlight.net\/forums\/<\/a>.<\/p>\n\n<\/p>\nWorkarounds<\/h2>\n
<\/font><\/h2>\n<\/h3>\n
Okay, almost there\u2026 we just need to work around one somewhat confusing bug in Blend you\u2019ll run into when you try to create a VB project:<\/p>\n
Prior to the announcement of Silverlight 1.1<\/a>, Silverlight plug-ins were written in XAML and Javascript. While the Javascript model is certainly powerful, using VB is always my preference\u2014it\u2019s a language I know well, and its flexibility suits my programming style. Not to mention that the introduction of VB.NET into the Silverlight world brings with it many of the .NET Framework\u2019s types and APIs I\u2019ve come to rely on.<\/p>\n If you\u2019ve had a chance to download the Silverlight 1.1 runtime<\/a>, you may have noticed that it\u2019s MUCH smaller than the full .NET Framework at 4.2 MB (and hopefully shrinking!). Clearly, some things have been factored out of the .NET Framework to keep the download size down and installation time short. And although a lot has been removed, the core set of types is included along with some APIs that are particularly useful for writing plug-ins\u2014things like a \u201clite\u201d version of System.Xml.dll, support for making web service calls, and so on. When deciding what aspects of the Visual Basic language and runtime should be included with Silverlight v1.1, we tried to follow a similar pattern: we wanted to preserve the core VB programming experience\u2014late binding, conversions, Linq, and so on; and we didn\u2019t want to bloat the download size with anything that wasn\u2019t absolutely necessary or didn\u2019t make sense in Silverlight\u2014things like some of the COM helpers (COM is not supported in Silverlight), financial functions, etc. It was a delicate balance to strike between functionality and overall size. The Silverlight 1.1 Alpha is our first crack at it\u2026 and it may be refined over the coming months with feedback. Here\u2019s a laundry list of what\u2019s supported\/not supported currently. (If you\u2019re interested in digging into the details, you can also view the types in the Object Browser using the tools described below.)<\/p>\n As a sort of test piece, I recently took a look at the Clock Sample<\/a> and wanted to see if the feature set we settled on enabled me to write VB code as I normally would for a Windows Forms or WPF application. The code basically just sets the minute, second, and hour hands on the clock to the current time (approximately). Here\u2019s what it looks like\u2026<\/p>\n ‘ Anonymous delegates, Handles–isn’t it pretty?<\/span><\/p>\n <\/span>Public<\/span> Sub<\/span> Canvas_Loaded() Handles<\/span> Me<\/span>.Loaded<\/span><\/p>\n <\/span>InitializeComponent()<\/span><\/p>\n <\/span>‘ Type inference; DateTime functions<\/span><\/span><\/p>\n <\/span>Dim<\/span> currentTime = Now<\/span><\/p>\n <\/span>‘ Conversions, type inference<\/span><\/span><\/p>\n <\/span>Dim<\/span> hourAngle = ((currentTime.Hour \/ 12) * 360 + currentTime.Minute \/ 2) + 180<\/span><\/p>\n <\/span>Dim<\/span> minAngle = ((currentTime.Minute \/ 60) * 360) + 180<\/span><\/p>\n <\/span>Dim<\/span> secAngle = ((currentTime.Second \/ 60) * 360) + 180<\/span><\/p>\n <\/span>‘ hourAnimation is a generated variable that makes use of WithEvents and Conversions<\/span><\/span><\/p>\n <\/span>‘ <\/span>Protected WithEvents hourAnimation As DoubleAnimation<\/span><\/span><\/p>\n <\/span>‘ <\/span>Me.hourAnimation = CType(Me.FindName(“hourAnimation”),DoubleAnimation)<\/span><\/span><\/p>\n <\/span>hourAnimation.From = hourAngle<\/span><\/p>\n <\/span>hourAnimation.To = hourAngle + 360<\/span><\/p>\n <\/span>minuteAnimation.From = minAngle<\/span><\/p>\n <\/span>minuteAnimation.To = minAngle + 360<\/span><\/p>\n <\/span>secondAnimation.From = secAngle<\/span><\/p>\n <\/span>secondAnimation.To = secAngle + 360<\/span><\/p>\n End<\/span> Sub<\/span><\/span><\/p>\n<\/blockquote>\n All in all, this particular example looks and feels pretty VB to me\u2014which isn\u2019t to say we\u2019ve nailed it by any means\u2026 but the example does give some indication as to the type of VB experience we\u2019re striving for with Silverlight. Let us know what you think.<\/p>\n Unless you\u2019re really into notepad , download the tools for Silverlight. The VS project templates alone are worth the bandwidth required, as they\u2019ll get you started in the right direction. In addition, many of the more interesting things you can do with Silverlight (e.g., animations, embedding videos, etc) are pretty tedious to wire-up by hand in XAML; using Expression Blend makes the process *much*<\/i><\/b> easier. All of the components mentioned below are available at: http:\/\/silverlight.net\/GetStarted\/<\/a>. I\u2019ve just included them here for convenience.<\/p>\n If you run into any problems getting this stuff installed, please post the problem at the forums, http:\/\/silverlight.net\/forums\/<\/a>.<\/p>\n <\/font><\/h2>\n<\/h3>\n Okay, almost there\u2026 we just need to work around one somewhat confusing bug in Blend you\u2019ll run into when you try to create a VB project:<\/p>\nSupported\u2026<\/i><\/b> <\/h4>\n
\n
\n
Not Currently Supported\u2026<\/i><\/b> <\/h4>\n
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\n
\n
Tools for building Silverlight Plug-ins with VB<\/font><\/h2>\n<\/h2>\n
\n
What to download<\/font><\/h2>\n<\/h3>\n
\n
\n
<\/p>\n
Workarounds<\/h2>\n
![](\"https:\/\/devblogs.microsoft.com\/vbteam\/wp-content\/uploads\/sites\/7\/2007\/05\/Blend_Error_thumb5B15D.png\")
<\/a><\/p>\n