Update JavaScript-Developer-I Test Question For Salesforce Certified JavaScript Developer I Certification

NEW QUESTION 1
Given the JavaScript below:
1 function filterDOM (searchString) {
2 const parsedSearchString = searchString && searchString.toLowerCase() ;
03 document.quesrySelectorAll(‘ .account’ ) . forEach(account => (
04 const accountName = account.innerHTML.toLOwerCase();
05 account. Style.display = accountName.includes(parsedSearchString) ? /*Insert code*/;
06 )};
07 }
Which code should replace the placeholder comment on line 05 to hide accounts that do not match thesearch string?

• A. ‘ name ’ : ‘ block ’
• B. ‘ Block ’ : ‘ none ’
• C. ‘ visible ’ : ‘ hidden ’
• D. ‘ hidden ’ : ‘ visible ’

Answer: B

NEW QUESTION 2
Refer to the code below: Let textValue = ’1984’;
Which code assignment shows a correct way to convert this string to an integer?

• A. let numberValue = Number(textValue);
• B. Let numberValue = (Number)textValue;
• C. Let numberValue = textValue.toInteger();
• D. Let numberValue = Integer(textValue);

Answer: A

NEW QUESTION 3
A developer wants to use a try...catch statement to catch any error that countSheep () may throw and pass it to a handleError () function.
What is the correct implementation of the try...catch?
A)

B)

C)

D)

• A. Option
• B. Option
• C. Option
• D. Option

Answer: A

NEW QUESTION 4
Refer to the code below:

After running this code, which result is displayed on the console?

• A. > true > false
• B. > 5 >undefined
• C. > 5 > -1
• D. >5 > 0

Answer: B

Explanation:

NEW QUESTION 5
A developer has the following array of student test grades: Let arr = [ 7, 8, 5, 8, 9 ];
The Teacher wants to double each score and then see an array of the students who scored more than 15 points.
How should thedeveloper implement the request?

• A. Let arr1 = arr.filter(( val) => ( return val > 15 )) .map (( num) => ( return num *2 ))
• B. Let arr1 = arr.mapBy (( num) => ( return num *2 )) .filterBy (( val ) => return val > 15 )) ;
• C. Let arr1 = arr.map((num) => num*2). Filter (( val) => val > 15);
• D. Let arr1 = arr.map((num) => ( num *2)).filterBy((val) => ( val >15 ));

Answer: C

NEW QUESTION 6
Refer to the code below: function changeValue(param) { Param =5;
}
Let a =10;
Let b =5; changeValue(b);
Const result = a+ “ - ”+ b;
What is the value of result when code executes?

• A. 10 -10
• B. 5 -5
• C. 5 - 10
• D. 10 - 5

Answer: A

NEW QUESTION 7
A developer at Universal Containers creates a new landing page based on HTML, CSS, and JavaScript TO ensure that visitors have a good experience, a script named personaliseContext needs to be executed when the webpage is fully loaded (HTML content and all related files ), in order to do some custom initialization.
Which statement should beused to call personalizeWebsiteContent based on the above business requirement?

• A. document.addEventListener(‘’onDOMContextLoaded’, personalizeWebsiteContext);
• B. window.addEventListener(‘load’,personalizeWebsiteContext);
• C. window.addEventListener(‘onload’, personalizeWebsiteContext);
• D. Document.addEventListener(‘‘’DOMContextLoaded’ , personalizeWebsiteContext);

Answer: B

NEW QUESTION 8
A developer implements a function that adds a few values.

Which three options can the developer invoke for this function to get a return value of 10 ? Choose 3 answers

• A. Sum () (20)
• B. Sum (5, 5) ()
• C. sum() (5, 5)
• D. sum(5)(5)
• E. sum(10) ()

Answer: CD

NEW QUESTION 9
Which option is a core Node,js module?

• A. Path
• B. Ios
• C. Memory
• D. locate

Answer: A

NEW QUESTION 10
Which statement parses successfully?

• A. JSO
• B. parse (""foo"');
• C. JSON.parse (""foo'");
• D. JSON.parse ("foo");
• E. JSON.parse ("foo");

Answer: A

NEW QUESTION 11
Which three browser specific APIs are available for developers to persist data between page loads ? Choose 3 answers

• A. IIFEs
• B. indexedDB
• C. Global variables
• D. Cookies
• E. localStorage.

Answer: ABE

NEW QUESTION 12
Universal Container(UC) just launched a new landing page, but users complain that the website is slow. A developer found some functions that cause this problem. To verify this, the developer decides to do everything and log the time each of these three suspicious functions consumes.
console.time(‘Performance’); maybeAHeavyFunction(); thisCouldTakeTooLong(); orMaybeThisOne(); console.endTime(‘Performance’);
Which function can the developer use to obtain the time spent by every one of the three functions?

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

Answer: A

NEW QUESTION 13
Refer to HTML below:
<p> The current status of an Order: <span id =”status”> In Progress </span> </p>.
Which JavaScript statement changes the text ‘In Progress’ to ‘Completed’ ?

• A. document.getElementById(“status”).Value = ’Completed’ ;
• B. document.getElementById(“#status”).innerHTML = ’Completed’ ;
• C. document.getElementById(“status”).innerHTML = ’Completed’ ;
• D. document.getElementById(“.status”).innerHTML = ’Completed’ ;

Answer: C

NEW QUESTION 14
Which function should a developer use to repeatedly execute code at a fixed interval ?

• A. setIntervel
• B. setTimeout
• C. setPeriod
• D. setInteria

Answer: A

NEW QUESTION 15
Refer to the following code that imports a module named utils:

Which two implementations of Utils.js export foo and bar such that the code above runs without error?
Choose 2 answers

• A.
• B.
• C.
• D.

Answer: BC

NEW QUESTION 16
developer creates a new web server that uses Node.js. It imports aserver library that uses events and callbacks for handling server functionality.
The server library is imported with require and is made available to the code by a
variable named server. The developer wants to log any issues that the server has while booting up.
Given the code and the information the developer has, which code logs an error at boost with an event?

• A. Server.catch ((server) => { console.log(‘ERROR’, error);});
• B. Server.error ((server) => { console.log(‘ERROR’, error);});
• C. Server.on (‘error’, (error) => { console.log(‘ERROR’, error);});
• D. Try{server.start();} catch(error) { console.log(‘ERROR’, error);}

Answer: C

NEW QUESTION 17
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