我为这样的作业提要创建了一个多维数组:
var jobs = [
["JOB222" , "Painter"],
["JOB333" , "Teacher"],
["JOB444" , "Delivery Driver"],
];
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我可以使用索引号访问数组
alert( jobs[2][1] ); // Alerts Delivery Driver
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如果我手动设置参考号,我可以遍历数组以找到匹配项.
var viewingJobRef = "JOB333";
for (var i=0;i<jobs.length;i++) {
if (jobs[i][0] == viewingJobRef) {
alert(jobs[i][1]); // This will alert Teacher
}
}
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所以我的问题是,是否可以直接访问数组而不使用循环?
var viewingJobRef = "JOB333";
alert( jobs[viewingJobRef][1] ); // I want this to alert Teacher
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Firefox错误控制台说: jobs [viewingJobRef]未定义,我该怎么办?
Zar*_*Dev 10
你想使用对象:
var jobs = {
"JOB222" : "Painter",
"JOB333" : "Teacher",
"JOB444" : "Delivery Driver"
};
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像这样访问:
var viewingJobRef = "JOB333";
alert( jobs[viewingJobRef] );
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要么
alert( jobs["JOB333"] );
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要么
alert( jobs.JOB333 );
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