Custom Attribute Sample (Attach a Custom Attribute to a Class)

[sukishan]

Custom Attribute Sample (Attach a Custom Attribute to a Class) 

In this sample, a custom attribute author is declared in J#, so it can be attached to (or target) all program elements.

The custom attribute is then attached to the class Point, and to the constructor of the class Point.

The class app reflects on the Point class and discovers if there are any custom attributes attached, and to what program elements they are attached.

Security Note 

This sample code is provided to illustrate a concept and should not be used in applications or Web sites, as it may not illustrate the safest coding practices. Microsoft assumes no liability for incidental or consequential damages should the sample code be used for purposes other than as intended.

Building and Running the Sample

To open the sample file in Solution Explorer

1. Click Download Sample.

The File Download message box appears.

Click Open, and on the left column of the zip folder window, click Extract all files.

The Extraction Wizard opens.

Click Next. You can change the directory that the files will be extracted to, and then click Next again.

Make sure that the Show extracted files check box is selected, and click Finish.

Double-click the sample's .sln file.

The sample solution is displayed in Solution Explorer. You might get a security warning that says the solution location is not trusted. Click OK to continue.

To build and run this sample

From the command line, type BUILD.bat.

Note 
See Building from the Command Line (Visual J#) for more information.


From the command line, type app.

Examine the output. Expected output:

Number of custom attributes on type Point are: 1
Number of methods (incl. constructors) on type Point are: 1
Method name: .ctor
Number of custom attributes on method: 2