如何在 JavaScript 中獲取物件的屬性值?
有一些方法可以查詢物件的屬性值,例如 `Object.values()`,但是使用此方法過程會很冗長。
我們可以藉助 `_.values()` 函式輕鬆查詢物件的屬性值,這是一個內建方法,屬於 underscore.js(一個提供多種功能的 JavaScript 庫)。
`_.values()` 方法無需迴圈即可獲取值,它是查詢物件屬性值的直接方法。
語法
_.values( object )
引數 - 此函式只接受一個引數,即物件。物件類似於陣列,具有鍵值對,但它不是陣列。
示例 1
以下是一個從物件中檢索值的示例:
<!DOCTYPE html>
<html>
<body>
<script src="//cdnjs.cloudflare.com/ajax/libs/lodash.js/0.10.0/lodash.min.js"></script>
</head>
<body>
<script>
var obj = {"name": 'Abcd kumar',age: 47, contact:9893444666, "Organization":'Spacex' }
var res = JSON.stringify(_.values(obj)); // we are using stringify because we want to print the value in page not in console.
document.write((res));
</script>
</body>
</html>
示例 2
在這個例子中,我們使用 `object.values()` 函式列印物件的屬性值。
<!DOCTYPE html>
<html>
<body>
<script src="//cdnjs.cloudflare.com/ajax/libs/lodash.js/0.10.0/lodash.min.js"></script>
</head>
<body>
<script>
var userDetails = {name: 'Aman Kumar',state:"Jharkhnad", work:'Technical Writer', company:"TutorialsPoint" };
for(let value of Object.values(userDetails)){
document.write(" " + value + " ");
}
</script>
</body>
</html>
示例 3
讓我們來看另一個例子:
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript"src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.1/underscore-min.js"></script>
</head>
<body>
<script type="text/javascript">
var details = _.values({
Name: "Vivek",
Address: "Noida Up",
Mobile: "+91 9876452301",
Email: "tutorialspoint@gmail.com",
});
//console.log(key);
for(let value of details){
document.write(" " + value + " ");
}
</script>
</body>
</html>
示例 4
這是一個示例,我們將物件的屬性值以陣列格式打印出來:
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript"src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.1/underscore-min.js"
></script>
</head>
<body>
<script type="text/javascript">
var details = _.values({
Name: "Vivek",
Address: "Noida",
Mobile: "+91 9876452301",
Email: "tutorialspoint@gmail.com",
});
var object = _.values({
name: "Aman Kumar",
Address: "Hyderabad",
Mobile: "+91 8252240532",
});
//console.log(key);
document.write("[");
for (let value of details) {
document.write(" " + value + " ");
} // here we are using for loop and documet.write() to display the value in page.
document.write("]");
document.write("[");
for (let x of object[2]) {
document.write(x); // get the third item from the list returned as well
}
document.write("]");
</script>
</body>
</html>
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