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Surrounded by Science: Learning Science in Informal Environments is designed to facilitate informal science learning. Based on the National Research Council study, Learning Science in Informal Environments: People, Places, and Pursuits , this book is a tool that provides case studies, illustrative examples, and probing questions for practitioners. Logical 3. NET Statement. The program passed the syntax or compiler test but fails during execution.
NET will trap the error and terminate the execution of the program. NET mechanism from terminating the program execution. NET cause the program execution to stop. NET will display a message indicating the nature of the error. NET to allow programmers to trap Run-time errors. This error can be caused by the user, logic or simply the system itself.
NET provides various error definitions that we can catch using the Catch with parameters for the unique error we are trapping for. Or simply trap all errors using the Catch block with no parameters. The statements inside the finally block are executed always. NET error mechanism which stopped execution of the program. Show "Exception was raised" MessageBox. The built-in VB. NET is powerful and offers a variety of features, but can be confusing.
NET an exception is really an Object which is either directly or indirectly derived from the Exception Class. What this means is that VB. NET provides a list of Exception classes each specifically design to trap a particular error.
Exception Class, VB. NET provides many standard exception classes for us to use in order to trap for a particular exception. Exception Class contains Properties and methods that we can access with information about the error. Exception Class traps all possible errors. Exception Class this class traps for all errors. I will not list the other properties. For further info. See VB. NET documentation. Methods of the Exception Class: Method Description GetType This method returns an Object which contains additional information about the type of error.
ToString Similar to the Message Property, but returns the a string containing the error and includes a lot more information about the error, such as path etc. I will not list the other methods. Trapping all Errors using the VB. Exception MessageBox. Both these code trap for all errors. As shown in the next example. NET class for this particular error. Show objException. ToString 'Use exception object's GetType. FullName Method to display name of error type MessageBox.
FullName MessageBox. NET provides many standard exception classes for us to use in order to trap for a specific error. We may want to trap for this error so that we can perform some corrective process etc. NET provides a variety of Classes for this purpose. Note that all these classes are derived from the main Exception Class. OverflowException Class to trap for this specific error only. NET error mechanism will take over and stop the program. Point is we need to be aware of this when trapping for specific errors.
Note that this only occurs with a floating point decimal number, not the integer data type. We will make some simple modifications to Example 7. Remember this exception is raised when we attempt to divide a Decimal Number by 0. Show " Caught a divide by zero exception" 'Use exception object's Message Property to display type of error MessageBox.
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