9

我是 javascript 新手，正在尝试通过 JSLint 进行验证。我应该在哪里放置“使用严格”以在全球范围内使用它并进行验证？

这给了我错误“语句位置出现意外的表达式'use strict'。”：

    "use strict";
    console.log('doing js in head-section');

    function helloWorld() {
        console.log('called function helloWorld()');
        alert('Hello World from a JS function showing an alert!');
    }

    function helloMyNumber() {
        console.log('called function helloMyNumber()');
        var max = 42;
        var yourLuckyNumber = prompt('Enter your lucky number (between 1 and '+ max +')');
        var myLuckyNumber = Math.floor(Math.random()*(max+1));
        var paragraph = document.getElementById('luckynumber');
        paragraph.innerHTML = paragraph.innerHTML + ' Your lucky number is: ' + yourLuckyNumber + '. Mine is: ' + myLuckyNumber + '. They ' + (yourLuckyNumber == myLuckyNumber ? 'DID ' : 'did NOT ') + 'match!';
    }



    console.log('doing JS in body-section');
    document.writeln('<p class="green">Hello World from JS within a body-section in HTML!</p>');
4

2 回答 2

6

根据文档，browserJSLint 的选项会自动禁用"use strict";全局级别的使用。据我所知，没有办法重新打开它。

您可以关闭浏览器选项，并browser使用以下方法获得与该选项相同的预先声明的全局变量：

/*global
Audio, clearInterval, clearTimeout, document, event, history, Image, location, name, navigator, Option, screen, setInterval, setTimeout, XMLHttpRequest
*/

或者，您可以将所有代码包装在 IIFE 中并"use strict";在其顶部使用。

或者，您可以切换到JSHint（有更多选项），并使用其选项在全局范围内strict: global允许。"use strict";

于 2016-02-09T16:55:17.980 回答
1

'use strict' 通常用在函数的开头。对于您的代码，我会将其全部包装在 IIFE 中，这将使“使用严格”有效

(function() {
    "use strict";
    console.log('doing js in head-section');

    function helloWorld() {
        console.log('called function helloWorld()');
        alert('Hello World from a JS function showing an alert!');
    }

    function helloMyNumber() {
        console.log('called function helloMyNumber()');
        var max = 42;
        var yourLuckyNumber = prompt('Enter your lucky number (between 1 and '+ max +')');
        var myLuckyNumber = Math.floor(Math.random()*(max+1));
        var paragraph = document.getElementById('luckynumber');
        paragraph.innerHTML = paragraph.innerHTML + ' Your lucky number is: ' + yourLuckyNumber + '. Mine is: ' + myLuckyNumber + '. They ' + (yourLuckyNumber == myLuckyNumber ? 'DID ' : 'did NOT ') + 'match!';
    }



    console.log('doing JS in body-section');
    document.writeln('<p class="green">Hello World from JS within a body-section in HTML!</p>');
})();
于 2016-02-09T16:51:13.973 回答