【笔记】JavaScript编码规范- 类型分配&强制转换

标签：javascript

执行强制类型转换语句。

String

// bad <p>// => this.reviewScore = 9;</p>
var A= this.reviewScore + '';


// good
var totalScore = '' + this.reviewScore;


// bad
var totalScore = '' + this.reviewScore + ' total score';


// good
var totalScore = this.reviewScore + ' total score';

var A= '4';

// bad
var val = new Number(A);

// bad
var val = +A;

// bad
var val = A>> 0;

// bad
var val = parseInt(A);

// good
var val = Number(A);


// good
var val = parseInt(A, 10);

// good
/**
* parseInt was the reason my code was slow.
* Bitshifting the String to coerce it to a
* Number made it a lot faster.
*/
var val = inputValue >> 0;

2147483647 >> 0 //=> 2147483647
2147483648 >> 0 //=> -2147483648
2147483649 >> 0 //=> -2147483647

var age = 0;

// bad
var hasAge = new Boolean(age);

// good
var hasAge = Boolean(age);

// good
var hasAge = !!age;

【笔记】JavaScript编码规范- 类型分配&强制转换

标签：javascript

原文地址：http://blog.csdn.net/princeterence/article/details/45843767