我们可以在 JavaScript 中检查一个属性是否在一个对象中吗?
以下是检查一个属性是否在 JavaScript 对象中的代码 −
示例
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Document</title>
<style>
body {
font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
}
.result {
font-size: 20px;
font-weight: 500;
color: blueviolet;
}
</style>
</head>
<body>
<h1>Checking a property in an object</h1>
<div class="result"></div>
<button class="Btn">CLICK HERE</button>
<h3>Click on the above button to check if firstName property is present in obj object</h3>
<script>
let resEle = document.querySelector(".result");
let obj = { firstName: "Rohan", lastName: "Sharma", age: 21 };
document.querySelector(".Btn").addEventListener("click", () => {
if (obj.hasOwnProperty("firstName")) {
resEle.innerHTML = "Object obj has firstName property";
} else {
resEle.innerHTML = "Object obj does not have firstName property";
}
});
</script>
</body>
</html>输出

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