The strict mode "use strict" in JavaScript, several mined areas to be noted:

1.with Statement throws Error

2. An undeclared variable is assigned a value error

3.arguments becomes static in strict mode, the parameters passed in are not related to arguments

4.delete will error

5. Duplicate attribute name of object will be error

6. Prohibit octal variables

7.eval is identified as the keyword, in addition to the eval parameter if there is a definition of the variable statement, in strict mode is just a trivial string, using typeof to detect the variable type defined in eval.

The strict mode "use strict" in JavaScript, several mined areas to be noted: