如何使用數組中的“ forEach”函數列出項目

Question

我需要列出帶有對象數組集的項目，但我無法獲得..請幫助我

<script>
var emp = [ {firstname: "raj", id:111, age:30; salary:3567},
            {firstname: "uva", id:222, age:35; salary:4567},
            {firstname: "pup", id:333, age:32; salary:7865},
            {firstname: "rav", id:444, age:33; salary:7654}];

var emplist = emp.length;

var doc = "<div>";
    for(i=0; i < emplist; i++){
        doc += "<p>" + emp[i].firstname + emp[i].id + emp[i].age + emp[i].salary + "</p>";
    }
    doc += "</div>";
    document.getElementById("demo2").innerHTML = doc;
</script>

Answer 1

您可以使用Array＃map方法進行迭代並生成單個p標簽，並使用Array＃join方法來將它們連接起來。

 <div id=demo2></div> <script> var emp = [ {firstname: "raj", id:111, age:30, salary:3567}, {firstname: "uva", id:222, age:35, salary:4567}, {firstname: "pup", id:333, age:32, salary:7865}, {firstname: "rav", id:444, age:33, salary:7654}]; document.getElementById("demo2").innerHTML = '<div>' + emp.map(empi => `<p>${empi.firstname} ${empi.id} ${empi.age} ${empi.salary}</p>`).join('') + '</div>'; </script> 

Answer 2

在定義對象數組時，您放置了一個; 在年齡值之后。

<script>
var emp = [ {firstname: "raj", id:111, age:30, salary:3567},
            {firstname: "uva", id:222, age:35, salary:4567},
            {firstname: "pup", id:333, age:32, salary:7865},
            {firstname: "rav", id:444, age:33, salary:7654}];

var doc = "<div>";
emp.forEach(function(empi){
    doc += "<p>" + empi.firstname + empi.id + empi.age + empi.salary + "</p>";
});
doc += "</div>";
document.getElementById("demo2").innerHTML = doc;
</script>

Answer 3

您可以只使用Object.values()和join()因為您要合並所有值。 並且還可以使用模板字符串來避免+重復。 我認為在這里使用map()更好。

 var emp = [ {firstname: "raj", id:111, age:30, salary:3567}, {firstname: "uva", id:222, age:35, salary:4567}, {firstname: "pup", id:333, age:32, salary:7865}, {firstname: "rav", id:444, age:33, salary:7654}]; document.getElementById("demo2").innerHTML = emp.map(Object.values).join('<p>'); 

 <div id="demo2"></div> 

如果您仍想使用forEach使用以下代碼段

 var emp = [ {firstname: "raj", id:111, age:30, salary:3567}, {firstname: "uva", id:222, age:35, salary:4567}, {firstname: "pup", id:333, age:32, salary:7865}, {firstname: "rav", id:444, age:33, salary:7654}]; var doc = "<div>"; emp.forEach(x => doc += `<p>${Object.values(x).join('')}</p>`) doc += "<div>" document.getElementById("demo2").innerHTML = doc; 

 <div id="demo2"></div>