JS-Dev-101 試験問題を無料オンラインアクセス

Given the JavaScript below:
function onLoad() {
console.log("Page has loaded!");
}
Where can the developer see the log statement after loading the page in the browser?

• A.On the terminal console running the web server
• B.In the browser performance tools log
• C.On the browser JavaScript console
• D.On the webpage console log

Universal Containers (UC) just launched a new landing page, but users complain that the website is slow. A developer found some functions that might cause this problem. To verify this, the developer decides to execute everything and log the time each of these three suspicious functions consumes.
01 console.time('Performance');
02
03 maybeAHeavyFunction();
04
05 thisCouldTakeTooLong();
06
07 orMaybeThisOne();
08
09 console.endTime('Performance');
Which function can the developer use to obtain the time spent by every one of the three functions?

• A.console.trace()
• B.console.timeStamp()
• C.console.timeLog()
• D.console.getTime()

After user acceptance testing, the developer is asked to change the webpage background based on the user's location. It works on the developer's computer but not on the tester's machine.
Which two actions will help determine accurate results?

• A.The developer should inspect their browser refresh settings.
• B.The tester should clear their browser cache.
• C.The developer should rework the code.
• D.The tester should disable their browser cache.

A developer is leading the creation of a new web server for their team that will fulfill API requests from an existing client. The team wants a web server that runs on Node.js, and they want to use the new web framework Minimalist.js. The lead developer wants to advocate for a more seasoned back-end framework that already has a community around it.
Which two frameworks could the lead developer advocate for?

• A.Next
• B.Gatsby
• C.Next.js
• D.Angular

JavaScript:
01 function Tiger() {
02 this.type = 'Cat';
03 this.size = 'large';
04 }
05
06 let tony = new Tiger();
07 tony.roar = () => {
08 console.log('They\'re great!');
09 };
10
11 function Lion() {
12 this.type = 'Cat';
13 this.size = 'large';
14 }
15
16 let leo = new Lion();
17 // Insert code here
18 leo.roar();
Which two statements could be inserted at line 17 to enable line 18?

• A.leo.roar = () => { console.log('They\'re pretty good!'); };
• B.leo.prototype.roar = () => { console.log('They\'re pretty good!'); };
• C.Object.assign(leo, Tiger);
• D.Object.assign(leo, tony);