我的代码有什么问题?它应该使用传入的数量在html中创建输入标签。
// Declare variables
var numberOfGrades = 0;
var NL = "\n";
// Functions
function setQuantity() {
numberOfGrades = document.getElementById("quantity").value;
var inputBox = document.createElement("INPUT");
var BR = document.createElement("br"); // Break line
var gradeNumber = 1;
var gradeText = document.createTextNode("Grade " + gradeNumber + ":");
for (var i = 0; i < numberOfGrades; i++) {
alert(numberOfGrades);
document.getElementById("formDiv").appendChild(BR);
document.getElementById("formDiv").appendChild(gradeText);
document.getElementById("formDiv").appendChild(inputBox);
gradeNumber++;
}
}
body {
font-family: "Open Sans", sans-serif;
}
.container {
width: 100%;
background-color: lightcyan;
padding: 10px;
}
<body>
<h1>Homework and Quiz average calculator</h1>
<p>Please Enter the required information to calcuate</p>
<div class="container" id="formDiv">
<form id="formID">
<p>
<strong>Calculate the average of homework grades</strong>
</p>
How many grades?
<input type="number" id="quantity" name="quantity" min="1" max="10" value="1">
<!--<input onclick="setQuantity()" type="submit" value="Apply">-->
</form>
<button onclick="setQuantity()">APPLY</button>
<br>
</div>
<script src="script.js"></script>
</body>
getElementById
的值缓存到一个变量中。例如,var formDiv = document.getElementById("formDiv");
并将其放在循环之前。这样你就不需要为每个成绩寻找该元素。速度方面并没有太大的区别,但可维护性会更好。 - Heretic Monkey