在JavaScript中有许多方法可以清空数组，下面本篇文章就来给大家介绍一些使用JavaScript清空数组的方法，希望对大家有所帮助。
方法一：将数组变量设置为大小为零的新数组
例：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>javascript清空数组</title>
</head>
<body style = "text-align:center;">
<p id = "up"></p>
<button onclick="empty()">
单击可清空
</button>
<p id = "down" style="color: green"></p>
<p id = "down1" style="color: green"></p>
<!-- 将数组大小设置为零 -->
<script>
var GFG_Array = [1, 2, 3, 4, 5];
var up = document.getElementById("up");
up.innerHTML = "GFG_Array："+GFG_Array;
var down = document.getElementById("down");
down.innerHTML = "GFG_Array的长度为："
+ GFG_Array.length;
function empty() {
GFG_Array = [];
down = document.getElementById("down");
down.innerHTML = "GFG_Array的长度为："
+ GFG_Array.length;
down1 = document.getElementById("down1");
down1.innerHTML = "GFG_Array："+GFG_Array;
}
</script>
</body>
</html>
效果图：
方法二：使用length属性将数组的长度设置为零
例：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>javascript清空数组</title>
</head>
<body style = "text-align:center;">
<p id = "up"></p>
<button onclick="empty()">
单击可清空
</button>
<p id = "down" style="color: green"></p>
<p id = "down1" style="color: green"></p>
<!-- 将数组大小设置为零 -->
<script>
var GFG_Array = [1, 2, 3, 4, 5];
var up = document.getElementById("up");
up.innerHTML = "GFG_Array："+GFG_Array;
var down = document.getElementById("down");
down.innerHTML = "GFG_Array的长度为："
+ GFG_Array.length;
function empty() {
GFG_Array.length = 0;
down = document.getElementById("down");
down.innerHTML = "GFG_Array的长度为："
+ GFG_Array.length;
down1 = document.getElementById("down1");
down1.innerHTML = "GFG_Array："+GFG_Array;
}
</script>
</body>
</html>
效果图：
方法三：使用pop方法连续删除数组元素，得到空数组
pop()方法用于删除并返回数组的最后一个元素，把数组长度减 1，并且返回它删除的元素的值。如果数组已经为空，则 pop() 不改变数组，并返回 undefined 值。
例：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>javascript清空数组</title>
</head>
<body style = "text-align:center;">
<p id = "up"></p>
<button onclick="empty()">
单击可清空
</button>
<p id = "down" style="color: green"></p>
<p id = "down1" style="color: green"></p>
<!-- 将数组大小设置为零 -->
<script>
var GFG_Array = [1, 2, 3, 4, 5];
var up = document.getElementById("up");
up.innerHTML = "GFG_Array："+GFG_Array;
var down = document.getElementById("down");
down.innerHTML = "GFG_Array的长度为："
+ GFG_Array.length;
function empty() {
while(GFG_Array.length > 0) {
GFG_Array.pop();
}
down = document.getElementById("down");
down.innerHTML = "GFG_Array的长度为："
+ GFG_Array.length;
down1 = document.getElementById("down1");
down1.innerHTML = "GFG_Array："+GFG_Array;
}
</script>
</body>
</html>
效果图：
注：这种方法比其他方法花费的时间更多，而且不太受欢迎。
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