我正在努力使“使用严格”;指令起作用,并且有一些麻烦。在以下文件中,FireFox 9将(正确)检测到未在第3行上声明someVar,但无法检测到在第19行上未声明theVar。

"use strict"; // this will cause the browser to check for errors more aggresively

someVar = 10; // this DOES get caught // LINE 3

// debugger; // this will cause FireBug to open at the bottom of the page/window
        // it will also cause the debugger to stop at this line

    // Yep, using jQuery & anonymous functions
$(document).ready( function(){
    alert("document is done loading, but not (necessarily) the images!");

    $("#btnToClick").click( function () {

        alert("About to stop");
        var aVariable = 1;
        debugger; // stop here!
        alert("post stop " + aVariable );

        // this lacks a "var" declaration:
        theVar = 10; // LINE 19  // this is NOT getting caught

        // needs a closing "
        // alert("hi);
        console.log("Program is printing information to help the developer debug a problem!");
    });

});

最佳答案

您需要在引发错误之前调用处理程序。换句话说,单击#btnToClick

fiddle 示例:http://jsfiddle.net/X3TQb/

关于javascript - 为什么 "use strict"(JavaScript)无法检测到未声明的变量?,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/8630541/

10-12 12:30
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