Web tech 512 MCQs - I wanted to share this document because it\'s useful for web tec PDF

Preview

Summary

I wanted to share this document because it's useful for web tech...

Description

Web tech 512 MCQ Consider the following code snippet: Var a = [1,2,3,4,5]; a.slice(0,3); what is the possible output for the above code snippet? Select one: Returns [1,2,3] Consider the following code snippet: Var tensquared = (function(x) {returns x*x;})10)); Will the above code work? Select one: Yes, perfectly Consider the following code snippet Function hypotenuse(a,b) { Function square(x) Return x*x; } Return Math.sqrt(squire(a) + square(b)); } What does the above code results? Select one: Sum of squire of a and b The pop() method of the array does which of the following task? Select one: decrements the total length by 1 The method or operator used to identify the array is Select one: typeof When does the function name become optional in JavaScript? Select one: When the function is defined as expressions Don function in JavaScript necessarily return a value? Select one: Few functions return values by default Consider the following code snippet:

If(!a[i]); continue What is the observation made? Select one: All of the option mentioned Consider the following code snippet: Var c = counter(), d = counter(); c.count() d.count() c.reset() c.count() d.count() The state stored in d is: Select one: 1 What is the difference between the two lines given below? !!(obj1&& obj2); (obj1 && obj2); Select one: The first line results in a real Boolean value whereas the second line merely checks for the existence of the objects Consider the following code snippet: Function constfuncs() { Var funcs = []; For (var i = 0; i < 10; i++)}; Return funcs; } Var funcs = constfuncs(); Funcs[5]() What does the last statement return? Select one: 10 For the below mentioned code snippet: Var = 0 = new Object();

The equivalent statement is: Select one: var o= new Object; The one-liner code that concatenates all strings passed into a function is Select one: function concatenate() { Return string.prototype.concat.apply{“,arguments); } If you have a function f and an object o, you can define a method named m of o with Select one: o.m=m.f; Consider the following code snippet : Var a = []; a.unshift(1); a.unshift(22); a.shift(); a.unshift(3,[4,5]; a.shift(); a.shift(); a.shift(); advertisements The final output for the shift() Is Select one: 1 If para1 is the DOM object for the paragraph, what is the correct syntax to change the text within the paragraph? Select one: para1.nodeValue=”New Text”: Class provides an interface for invoking JavaScript methods and examining JavaScript properties. Select one: JSObject Which best explains getSelection()?

Select one: Returns the value of cursor-selected text What are variables used for in HavaScript Programs? Select one: Storing numbers, dates, or other values To open a dialog box each time an error occurs,which of the following is added to prefs.js? Select one: user_pref(“javascript.classic.error_alerts”, true); Choose the client-side JavaScript object? Select one: FileUpLoad Scripting language are Select one: High Level Programming language The syntax of capture events method for document object is Select one: captureEvents(eventType) Which of the following is the structure of an if statements? Select one: If(conditional expression is true) {then execute this code>->} When a javaScript object is sent to Java, the runtime engine creates a java wrapper of type Select one: JSObject Which of the following is not valid JavaScript variable name? Select one: 2names Tag is an extension to HTML that can enclose any number of JavaScrip statements. Select one: Choose the server-side JavaScript object? Select one: File In JavaScript is an object of the target language data type that encloses an object of the source language Select one: a wrapper Which of the following can’t be done with client-side JavaScript? Select one: Storing the form’s contents to a database file on the server JavaScript is also called client-side JavaScript Select one: Navigator To automatically open the console when JavaScript error occurs which of the following is added to prefs.js? Select one: user_pref(“javascript.console.open_on_error”, true); What is the correct JavaScript syntax to write “Hello World”? Select one: document.write(“Hello World”) Which of the following is not considered a JavaScript operator? Select one: this Inside which HTML element do we put the JavaScript? Select one: Select one: 78 Which is the correct way to write a JavaScript array? Select one: var txt = new Array(“tim”,”kim”,”jim”) Method evaluates a string of JavaScript code in the context of the specified object. Select one: Eval The keydown event occurs when a viewer presses down a key on the keyboard. Select one: True Which of the following function of Array object adds one or more elements to the end of an array and returns the new length of the array? Select one: push() To set up the window to capture all click events, we use which of the following statement? Select one: window.captureEvents(Event.CLICK); Which of the following function of string object extracts a section of a string and returns a new string? Select one: slice() Which of the following event fires when the form element loses the focus: , ,,,? Select one: onblur Which of the following function of Number object returns the number’s value? Select one: valueOf() The array Select one: Splice

method of an Array object adds and/or removes elements from an

Which built-in method returns the length of the string? Select one: length() Can you pass a anonymous function as an argument to another function? Select one: true Which tags(s) can handle mouse events in Netscape? Select one: To enable data tainting, the end user sets the

environment variable.

Select one: NS_ENABLE_TAINT Is the tainted property of a window object Select one: Defaultstatus To set up the window to capture all click events, we use which of the following statements? Select one: window.captureEvents(Event.CLICK); Which of the following is a valid type of function javaScript supports? Select one: All of the option mentioned. Which built-in method returns the calling string value converted to lower case Select one: toLowerCase() Which of the following function of Array object sorts the elements of an array? Select one: sort() Which built-in method combines the text of two strings and returns a new string? Select one: concat() The syntax of close method for document object is

Select one: Close() The mousedown event uses what keyword as its event handler? Select one: mousedown What is the output of the below code?

Var s = “9123456 or 80000?”; Var pattern = /\d{4}/;

Var output = s.match(pattern); Document.write(output);

Select one: 9123 Which of the following function of string object returns the index within the calling String object of the last occurrence of the specified value? Select one: lastIndexOf() Which of the following is correct about JavaScript? Select one: All of the option mentioned. Which of the following function of Array object applies a function simultaneously against two values of the array (from left-to-right) as to reduce it to a single value? Select one: reduce() What is the purpose of the basic validation? Select one: Mere data existence What would happen if the data in the client had been wrong? Select one: Sends back the data and waits for correction What is the purpose of the mimeTypes property of a plug-in entry Select one: Contains MIME types Which of the following is the child object of the JavaScript navigator? Select one: Plugins What is it called when we make a mistake in the script? Select one: Bug Which of the following is the definition for debugging? Select one: Finding bugs and Fixing bugs Which of the following are the properties of a plug-in entry? Select one: All of the option mentioned How do we debug a script? Select one: Use of JavaScript Validato and Use of JavaScript Debugger Where is the error icon shown in the internet Explore? Select one: Status bar

What kind of error notifications are shown in the console window? Select one: Syntax error and Runtime error...