qr code generator asp net c# AssemblyFlagsAttribute Class in Visual C#.NET

Encoder QR Code 2d barcode in Visual C#.NET AssemblyFlagsAttribute Class

The AssemblyFlags attribute is used to specify one or more of the AssemblyNameFlags values to the assembly. The AssemblyNameFlags enumeration is detailed in Table 14-6.

Description Enables the just-in-time (JIT) compiler optimization Enables the just-in-time (JIT) compiler tracking No flags are in effect Enables creation of the public key of the assembly to be based on the actual public key specified instead of on the public key token Allows for the assembly to be retargeted to an assembly from a different publisher

You can use the AssemblyFlags attribute by specifying one or more of the AssemblyNameFlags enumerations, as shown in the following example:

' VB <assembly: _ AssemblyFlags(AssemblyNameFlags.EnableJITcompileOptimizer Or _ AssemblyNameFlags.EnableJITcompileTracking)> // C# [assembly: AssemblyFlags(AssemblyNameFlags.EnableJITcompileOptimizer | AssemblyNameFlags.EnableJITcompileTracking)]

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The AssemblyInformationalVersion attribute is used to specify a version that is used just for information purposes. The runtime never uses this version for runtime versioning or side-by-side versioning of the assembly. The following lines of code show how to use this attribute:

' VB <Assembly: AssemblyInformationalVersion("1.0.0.1")> // C# [assembly: AssemblyInformationalVersion("1.0.0.1")]

The AssemblyKeyFile attribute is used to specify the path to a key file to use to sign (or strongly name) this assembly. The sn.exe tool that ships with the .NET Framework SDK can be used to create a key file. To use this attribute, specify the full path to a key file, like so:

' VB <Assembly: AssemblyKeyFile("../key.snk")> // C# [assembly: AssemblyKeyFile("../key.snk")]

The AssemblyTitle attribute is used to specify a title for this assembly in the manifest, as shown in the following example:

' VB <Assembly: AssemblyTitle("Proseware.Framework.DataLayer")> // C# [assembly: AssemblyTitle("Proseware.Framework.DataLayer")]

The AssemblyTrademark attribute is used to specify any trademark information about this assembly, as shown in the following example:

' VB <Assembly: AssemblyTrademark("Proseware ")> // C# [assembly: AssemblyTrademark("Proseware ")]

The AssemblyVersion attribute is used to specify the version of the assembly. The assembly version is made up of four elements separated by period:

<major version>.<minor version>.<build number>.<revision> For example, 1.2.3.4

The AssemblyVersion attribute allows you to replace the build number and the revision with an asterisk. Using the asterisk tells the compiler to update the build number and revision with an autogenerated value. The autogenerated build number is an autoincrementing number that updates once per day. The autogenerated revision number is a randomly generated number. If you specify a revision number, you cannot use an asterisk for the build number. You can specify the AssemblyVersion using the attribute, like so:

' VB <Assembly: AssemblyVersion("1.2.*.*")> // C# [assembly: AssemblyVersion("1.2.*.*")]

Setting attributes on an assembly is only part of the job. You also need to be able to get the attributes for an assembly. The main way you can get the attributes is by calling the GetCustomAttributes method on the Assembly class. This method is part of the ICustomAttributeProvider interface. The ICustomAttributeProvider interface is used to find what types of objects provide custom attributes. Because of this, the GetCustomAttribute allows for a Boolean value to indicate whether to get inherited attributes. As you will see in Lesson 3, this is a very useful idea. But because GetCustomAttributes is on the Assembly class, the .NET Framework completely ignores the Boolean value. (There is no inheritance tree for assemblies.) You can call the GetCustomAttributes method to get all the attributes on the assembly, like so:

' VB Dim a As Assembly = Assembly.GetExecutingAssembly() Dim attrs() As Object = a.GetCustomAttributes(false) For Each attr As Attribute In attrs Console.WriteLine("Attribute: {0}", attr.GetType.Name) Next

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// C# Assembly a = Assembly.GetExecutingAssembly(); object[] attrs = a.GetCustomAttributes(false); foreach (Attribute attr in attrs) { Console.WriteLine("Attribute: {0}", attr.GetType().Name); }

In cases where you need to get a specific attribute, you can call the GetCustomAttributes method and specify the type of the attribute you are looking for. Here is an example of getting the AssemblyDescription attribute:

' VB Dim a As Assembly = Assembly.GetExecutingAssembly() Dim attrType As Type = GetType(AssemblyDescriptionAttribute) Dim versionAttrs() As Object = a.GetCustomAttributes(attrType, false) If (versionAttrs.Length > 0) Then Dim desc As AssemblyDescriptionAttribute = _ CType(versionAttrs(0), AssemblyDescriptionAttribute) Console.WriteLine("Found Description!") Console.WriteLine("Desc: {0}", desc.Description) End If // C# Assembly a = Assembly.GetExecutingAssembly(); Type attrType = typeof(AssemblyDescriptionAttribute); object[] versionAttrs = a.GetCustomAttributes(attrType, false); if (versionAttrs.Length > 0) { AssemblyDescriptionAttribute desc = (AssemblyDescriptionAttribute)versionAttrs[0]; Console.WriteLine("Found Description!"); Console.WriteLine("Desc: {0}", desc.Description); }