Learning content issues:
- Which two engines are the browsers composed of?
- The execution process of Js code in the browser
- The composition of the main content of Js?
- Three types of writing position classification of Js
- What is Js annotation and how to achieve it
- What is the representation of the string entered in the js method, such as entering a string in alert
Reasons for selection: These problems are precautions or principles in use.
Specific answer:
- The execution process of the Js code in the browser
a) The Js code is executed in a single thread through the js engine in the browser. And every time a sentence of code is interpreted, a code is executed. - Which engine is the browser composed of?
a) Rendering engine, js engine
b) Rendering engine is mainly used to execute html, css code
c) Js engine mainly executes js code - What is the composition of Js?
a) Js is composed of ECMAScript, DOM, and BOM?
b) ECMAScript is the js code standard
c) DOM is the objectification of html and css, allowing js to operate
d) BOM objectification of common functions of the browser , You can let js operate - Three writing positions of Js
a) Inline, inline, external reference - Js comment?
a) // or /* code*/
b) // shortcut key ctrl+/
c) /* code*/ shortcut key shift+alt+a - What is the representation of the string entered in the js method, such as entering a string in alert.
a) Use single quotation marks