Summary of javascript code specifications

Source: Internet
Author: User

1. Javascript code should comply with Douban-JSLint test standards

1-1. The statement must end with a semicolon, except for, function, if, switch, try, while

1-2. Only long statements can be considered to be disconnected, for example:

TEMPL_SONGLIST.replace ('{TABLE}', da ['result'])
. Replace ('{PREV_NUM}', prev)
. Replace ('{NEXT_NUM}', next)
. Replace ('{CURRENT_NUM}', current)
. Replace ('{TOTAL_NUM}', da. page_total );

To avoid conflicts with the JSLint validation mechanism, operators such as "." or "+" are placed at the end of the line. The code above should be changed:

TEMPL_SONGLIST.replace ('{TABLE}', da ['result']).
Replace ('{PREV_NUM}', prev ).
Replace ('{NEXT_NUM}', next ).
Replace ('{CURRENT_NUM}', current ).
Replace ('{TOTAL_NUM}', da. page_total );

1-3. Avoid extra commas. For example, var arr = [1, 2, 3,];

1-4. All cyclic bodies and judgment bodies must be included in. For example:


If (condition)
If (condition) statement;


If (condition ){
Statement; or
If (condition) {statement ;}

1-5. in the for-in loop body, you must use the hasOwnProperty method to check whether the member is a member of itself. Avoid contamination from the prototype chain.

1-6. Variable declaration. The variable declaration should be placed at the top of the function. Avoid using undeclared variables.


If (n> 0 ){
Var isvalid = true;


Var isvalid;
If (n> 0 ){
Isvalid = true;

1-7. Do not use with, void, or edevil.

1-8. Use a strict condition operator. Use = instead of =, use! = Replace! =.

1-9. the following types of objects are not recommended to be constructed using new: new Number, new String, new Boolean, new Object (replaced by {}), and new Array (replaced ).

1-10. The reference object member uses obj. prop1 to replace obj ["prop1"] unless the attribute name is a variable.

Note: Douban-JSLint is a customized JSLint.

Note: If you want to skip the JSLint check by using other global variables in the module code, you can add a declaration to the file, such:

2. Javascript naming rules

2-1. uppercase letters of the constructor. For example:

Function Dialog (config ){
} Var dlg = new Dialog ({...});

2-2. The property or method name of the object uses the lower camel-case method, such as "init", "bindEvent", "updatePosition ":

Dialog. prototype = {
Init: function (){},
BindEvent: function (){},
UpdatePosition: function (){}};

2-3. The private variable name starts with an underscore. For example, "_ current", "_ defaconfig config"

2-4. All constant names are capitalized and words are separated by underscores. For example, "CSS_BTN_CLOSE" and "TXT_LOADING"

2-5. prefix of variable name:






I, j, k, m, n, etc .*

Integer as counter/iterator

(For I = 0; I <= oArray. length; I ++)





Is, can, has


[Boolean name] ConditionName

Event method

Event attachment

[Event type] _ MethodName

Accessor method


Accessor method


Note: Only a counter/iterator shoshould use a single-letter designation.

3. Code formatting requirements

3-1. Necessary spaces and indentation in the statement

3-1-1. It must be followed by spaces before and after the "()" used to contain the statement, such as: if/for/while/switch (statements ){... }

3-1-2. "=" must be followed by Spaces

3-1-3. "," between array members must be followed by a space


For (t in selected) {if (! Hash [t]) deselect (t )}


For (t in selected ){
If (! Hash [t]) {
Deselect (t );}

3-2. Use a long statement to disconnect rows:


TEMPL_SONGLIST.replace ('{TABLE}', da ['result']). replace ('{PREV_NUM}', prev ). replace ('{NEXT_NUM}', next ). replace ('{CURRENT_NUM}', current ). replace ('{TOTAL_NUM}', da. page_total );


TEMPL_SONGLIST.replace ('{TABLE}', da ['result']).
Replace ('{PREV_NUM}', prev ).
Replace ('{NEXT_NUM}', next ).
Replace ('{CURRENT_NUM}', current ).
Replace ('{TOTAL_NUM}', da. page_total );

3-3. Format object parameters:


EmbedSWF (id, {url: '/swf/player30792.swf? Url = '+ el. href, width: 261, height: 30, params: {wmode: 'transparent'}, attributes: {id: "player-sample" + I, name: "player-sample" + I }});

Good:Copy codeThe Code is as follows: embedSWF (id ,{
Url: '/swf/player30792.swf? Url = '+ el. href,
Width: 261,
Height: 30,
Params: {wmode: 'transparent '},
Attributes :{
Id: "player-sample" + I,
Name: "player-sample" + I

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