Summary of JavaScript debugging _ ax

Declaration: This post is really gold-rich, so I am afraid you will enter Baoshan!

The reason for not doing this is:
① The original has been written.
1. There is no such email number, or the email name is incorrect.
2. When the HTML control value is obtained, the row cannot be merged because the obtained result is incorrect.
3. The syntax is incorrect. See note 1.
② The HTML control and function name are the same

I have encountered the following situations:
1. I wrote half a bracket and checked it for half a day.
2. Generally, name is used for retrieving objects. See note 2.
3. debugging is really difficult. You can only use alert (); statement to try again without syntax check.Who has a good idea ??
4. Chinese characters cannot be entered as ID/name !!, You don't believe it? Just give it a try.
5. Dropped a concatenation string's +
6. When I write my previous postCodeWrite comments and forget to cause the comments.
7. The for statement is written as follows: For (INT I = 0; I <5; I ++) {} seems to be correct. Check for n times. Why? Q: What is int type ????
Positive Solution:
For (VAR I = 0; I <5; I ++ ){}

Note 1: I used a switch statement. In the syntax, there is no break after case, and I did not write it myself. The result can be imagined: I executed each case once, there may be a small error in the original good help materials. One word: Wu!
NOTE 2:Remember: Obtain all HTML controls using their names, such as: document. mailform. mailselect. value; among them, mailform mailselect is the control name, only one case will use ID: document. getelementbyid ("ax"); where ax is the ID of a control, and the getelementbyid () method is the method of the Document Object. In other words, getelementbyid can only be used after the document, it's all about Dom !!!How can no one tell new people about such an important thing?

[Conclusion] The baseline encoding method is not practical. When writing JavaScript code, it fails to develop a good encoding format, and even a low-level mistake such as dropping parentheses occurs (maybe I deleted a few when I deleted them, if I did not write one at the time of writing, I wouldn't believe it when I killed it, and I wrote the parentheses in pairs.) I read the first ten chapters of this DHTML book two days ago, for HTML, CSS, javaScript and Dom have a closer understanding. I hope you can take a look at this book.