HTML DOM中的Storage length屬性用於返回存儲在存儲對象中的項目數。存儲對象包括localStorage或sessionStorage。
用法:
獲取存儲長度屬性。
object.length
返回值:它返回一個數字,指示存儲對象中當前的項目數。
示例1:在localStorage對象上使用。
<!DOCTYPE html>
<html>
<head>
<title>DOM Storage length</title>
</head>
<body>
<h1 style="color:green">
GeeksForGeeks
</h1>
<b>DOM Storage length</b>
<p>Click on the buttons below to add/clear
items and check the current number
of items in localStorage
</p>
<p>Total Items:<span class="output"></span></p>
<button onclick="addItem(50)">
Add 50 items
</button>
<button onclick="clearItems()">
Clear all items
</button>
<button onclick="getStorageLength()">
Get Storage length
</button>
<div class="items"> </div>
<script>
// To set item.
function addItem(values) {
for (i = 0; i < values; i++)
localStorage.setItem(i, 'item ' + i);
}
// To clear item.
function clearItems() {
localStorage.clear();
}
// To return the number of items.
function getStorageLength() {
totalItems = localStorage.length;
document.querySelector('.output').textContent =
totalItems;
}
</script>
</body>
</html>
輸出:添加50個元素並單擊按鈕之後。
示例2:在sessionStorage對象上使用
<!DOCTYPE html>
<html>
<head>
<title>DOM Storage length</title>
</head>
<body>
<h1 style="color:green">
GeeksForGeeks
</h1>
<b>DOM Storage length</b>
<p>
Click on the buttons below to add/clear
items and check the current number of
items in sessionStorage
</p>
<p>Total Items:<span class="output"></span></p>
<button onclick="addItem(10)">Add 10 items</button>
<button onclick="clearItems()">Clear all items</button>
<button onclick="getStorageLength()">
Get Storage length
</button>
<div class="items"> </div>
<script>
function addItem(values) {
for (i = 0; i < values; i++)
sessionStorage.setItem(i, 'item ' + i);
}
function clearItems() {
sessionStorage.clear();
}
function getStorageLength() {
totalItems = sessionStorage.length;
document.querySelector('.output').textContent =
totalItems;
}
</script>
</body>
</html>
輸出:添加10個元素後,單擊按鈕。
支持的瀏覽器:下麵列出了存儲長度屬性支持的瀏覽器:
- 穀歌瀏覽器4.0
- Internet Explorer 8.0
- Firefox 3.5
- Opera 10.5
- Safari 4.0
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注:本文由純淨天空篩選整理自sayantanm19大神的英文原創作品 HTML | DOM Storage length Property。非經特殊聲明,原始代碼版權歸原作者所有,本譯文未經允許或授權,請勿轉載或複製。