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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