Lab 9: Error Handling Trong phòng thí nghiệm này, bạn sẽ tìm hiểu làm thế nào để chèn xử lý lỗi đơn giản vào JMart kịch bản và ném các thông báo lỗi tùy chỉnh cũng như đánh bắt cơ bản JavaScript tin nhắn. Mỗi tập thể dục bao gồm một phần "Mục tiêu" mô tả mục đích của tập thể dục. Bạn được khuyến khích để cố gắng hoàn thành bài tập từ thông tin được đưa ra trong phần Mục tiêu. Nếu bạn cần thêm thông tin để hoàn thành việc tập thể dục, phần Mục tiêu được theo sau bởi bystep bước. | JavaScript Debugging Lab 9 Error Handling TIP Because this lab includes a great deal of typed code we ve tried to make it simpler for you. You will find all the code in and in the same directory as the sample project. To avoid typing the code you can cut paste it from the source files instead. Feb 19 2008 3 29PM Dao Dung dungdq@ For productvevaluation only- nOt for distribution or commercial use. Copyright 2003 by Application Developers Training Company All rights reserved. Reproduction is strictly prohibited. 9-27 Lab 9 Error Handling Lab 9 Overview In this lab you will learn how to insert simple error handling into the JMart script and to throw custom error messages as well as catching basic JavaScript messages. To complete this lab you ll need to work through three exercises and optionally the third exercise for the Venkman Debugger Bullet-Proof Functions Nested Try Catch Venkman Test Each exercise includes an Objective section that describes the purpose of the exercise. You are encouraged to try to complete the exercise from the information given in the Objective section. If you require more information to complete the exercise the Objective section is followed by detailed step-by-step instructions. Feb 19 2008 3 29PM Dao Dung dungdq@ For productevaluation only- nOt for distribution or commercial use. JavaScript Copyright 2003 by Application Developers Training Company All rights reserved. Reproduction is strictly prohibited. ppDev Bullet-Proof Functions Bullet-Proof Functions Objective In this exercise you will set up error handling in the two main functions of the JMart application. Most functionality will be encapsulated and each try catch block will utilize a finally block as well. Things to Consider While this exercise captures almost any functionality it is not necessary to wrap an entire function into try catch blocks when the code obviously will not produce errors such as in default variable .
