From Xojo Documentation

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The Language Reference gives you fast access to information about all the Xojo programming language elements: objects, keywords, operators, constants, error messages, runtime exceptions, built-in methods and functions, and so forth. Wherever applicable, the properties and methods belonging to an object are documented, along with cross-references to related objects.

How to Use the Language Reference

To display the Language Reference, choose Language Reference from the Xojo Help menu.

Searching the Language Reference

Use the Search entry area on top right of the Xojo Documentation site to search the Language Reference. To search for a keyword, class, method or anything else, begin typing the name of the object.


Property names in bold are read-only at runtime (they also are displayed with a small lock icon). This means that your code can read their values but cannot change their values.

Optional Parameters in syntax statements are surrounded by brackets- [ ].

Items in blue underline are hypertext links to other parts of the Language Reference.

In some cases, code that is irrelevant to the example is omitted for sake of clarity. Omitted code is indicated by bullets.

Code examples in the Language Reference are surrounded by a gray rectangle. You can drag any code example into your Code Editor and try it out. The code examples work as shown in the Language Reference with two exceptions: In a few cases, the Sub or Function declaration line is included in the code example because variables that are included in the example are declared in this line rather than via Dim statements within the method. When you drag such an example into your Code Editor, you must delete the (redundant) Sub or Function statement and be sure that the variables are declared in your own method's declaration line. Second, please keep in mind that code examples for Error Messages and Runtime Exceptions are designed to fail.