freeCodeCamp/guide/chinese/certifications/javascript-algorithms-and-d.../basic-javascript/testing-objects-for-properties/index.md

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---
title: Testing Objects for Properties
localeTitle: 测试属性的对象
---
## 测试属性的对象
这是一个例子:
```javascript
// Setup
var myObj = {
gift: "pony",
pet: "kitten",
bed: "sleigh"
};
function checkObj(checkProp) {
// Your Code Here
return "Change Me!";
}
// Test your code by modifying these values
checkObj("gift");
```
这是一个解决方案:
我们在这里不做任何改动:
```javascript
// Setup
var myObj = {
gift: "pony",
pet: "kitten",
bed: "sleigh"
};
```
此外,在函数体中我们使用`.hasOwnProperty(propname)`对象方法来确定该对象是否具有给定的属性名称。带有布尔值的`if/else`语句将帮助我们:
```javascript
function checkObj(checkProp) {
// Your Code Here
if (myObj.hasOwnProperty(checkProp) == true) {
return myObj[checkProp];
}
else {
```
and change the value of `return` in `else` statement:
```
JavaScript的 返回“未找到” } }
```
Now, you can change `checkObj` values:
```
JavaScript的 //通过修改这些值来测试代码 checkObj “礼物”);
```
Here's a full solution:
```
JavaScript的 function checkObjcheckProp{ //你的代码在这里 ifmyObj.hasOwnPropertycheckProp== true{ return myObj \[checkProp\]; } 其他{ 返回“未找到” } } //通过修改这些值来测试代码 checkObj “礼物”); \`\`\`