#
JavaScript 	
 HTML  webPC
### 1.1 
1. HTML
2. 
3. HTML
4. 
5. 
6. cookies
7. Node.js  
   
### 1.2 				
**ECMAScript**	
**DOM**			
**BOM**   
 
## 2 
### 2.1 JavaScript 
JavaScript  
JavaScript`try{}catch(){}`		
![Image of trycatch]		
(https://github.com/sammulyuan/javascript/blob/master/images%20/trycatch.png)  

1. Javascript		
2. V8SpiderMonkeyV8JavascriptSpiderMonkeyC++		
3. C  
             
### 2.2  

1. 
2. HTML
3. HTMLjs
4. WindowsLinuxMacAndroidiOS  
      
### 2.3 

- **TestSwarm**MozillaJavaScript
- **Minimee**MinimeeCSSJavaScript
- **Doctor JS**Doctor JS  JavaScript 
- **Remy Sharps JSConsole** JavaScript 
- **JavaScript Library Boilerplate**JavaScript Library Boilerplate  JavaScript 
- **Jsdoc-toolkit**JsDoc Toolkit  JavaScript API
- **Jasmine  BDD for your JavaScript**Jasmine javascript
- **ObfuscateJS: JavaScript compressor** JavaScript 
- **PEG.js**PEG.js JavaScript
- **JSONView**JSONView JSONFirefox
- **JSonduit**JSonduit  JSON 
- **Jsplumb**JsPlumb jQueryMooTools  YUI3
- **Helma:** Helma WebJavaScript 
- **HTML + JSON Report** JSON HTML
- **JSON Editor** JSON 

## 3 JavaScript
### 3.1 JavaScript
- ``JavaScriptJavaScript``

```
	                 
```		

  JavaScript  //  		

JavaScriptJavaScript*.js `
```	

- ````
- `` 

### 3.2 JavaScript 

1. JavaScriptvar
2. JavaScript
3. JavaScript 
  
### 3.3 JavaScript  

1. JavaScript JavaScript  x=2z=x+y
	1.  x  y age, sumtotalvolume
	2. 
    3.  $  _ 
    4. y  Y 
      
    > JavaScript  JavaScript 	JavaScript

2. 
 	1. function
	2.  function 
	
**JavaScript **

 JavaScript 
		
- ** var **`var name`;		
- `carname=Hello"`;	
- ****`var name=Hello`	
- **** var `var name="Hello", age=22, job="CEO"`;
- ****		


```javascript				
var name="Hello",		
age=22		
job="CEO";
```
-  undefined
-  name  undefined`var name`;

** JavaScript **		
 JavaScript 	
 name  Hello"	

	

```javascript
var carname="Volvo";		
var carname;
```

### 3.4 JavaScript   
**JavaScript**		

 |   |  |  | 		 
------  | ------ | ------ | ----- | ------	
+ |  |  | 2+3 | 5
- |  |  | 3-2 | 1
* |  |  | 2*3 | 6
/ |  |  | 9/3 | 3
% |  |  | 12%5 | 2
++ |  | x++++x | x=3	| x=x++=4		x=++x=3
-- |  | 1| x=3	| x=x--=3		x=--x=2

**JavaScript **		

 x=y  y  x

 x=10  y=5

 |  |   |  
----- | ---- | ----- | -----
= |  x=y | |  x=5
+= | x+=y | x=x+y | x=15
-= | x-=y | x=x-y | x=5
\*= | x\*=y | x=x*y | x=50
/= | x/=y | x=x/y | x=2
%= | x%=y | x=x%y | x=0
^= | x^=y | x=x^y1true0false | x=15

**JavaScript **		
+		
+		
		
			
```
txt1="What a very";
txt2="nice day";
txt3=txt1+txt2;
txt3  "What a verynice day"
```
		
		
```
txt1="What a very ";
txt2="nice day";
txt3=txt1+txt2;
```
		
		
```
txt1="What a very";
txt2="nice day";
txt3=txt1+" "+txt2;
```
 txt3 "What a very nice day"

- `substring(index1,index2)`		
- `length`		
- `charAt(index)`
- ()		
	`indexOf(string)`		
    `lastIndexOf(string)`
          
### 3.5 JavaScript   		
**JavaScript **		
true  false	
		
 x=1  y=2 
	
 |  |  |  |  		
----- | ---- | --- | ---- | ----   
== |  | truejavascript | 3 == x  	3== y	3== 3 | false false true  
!= |  | true | x!= 4	y != 2 | true	false
=== |  | true | 3===3	x===1 | false	true
!== |  | true | 3!==  3	 x!== 1 | true	false
\> |  | true | x > y | false
\>= |  | true | y >= x | true
< |  | true | x < y | true