JS leackage Check 1

1.JS is case sensitive. Use the Unicode character set. Ignore extra spaces

2. The document.write () method writes the contents to an HTML document. Note: If document.write is executed after the document has finished loading, the entire HTML page will be overwritten.

3. Console.log () is primarily handy for your modal JavaScript, and you can see what you are outputting in the page.

His advantages compared to alert are:

He can see the structure of things, if it is alert, fade out an object is [Object Object], but the console can see the contents of the object.

Console does not interrupt the operation of your page, if you use alert to bounce out the content, then the page is dead, but the console output after your page can be normal operation.

4.for. in; break;continue;

5.var Carname; the value of the variable carname will be undefined;

var carname= "Volvo";
var carname;

　　If you re-declare a JavaScript variable, the value of the variable is not lost;

6.

JS leackage Check 1