Javascript Comparison Operators
Javascript comparison operators are used to compare two values and return a boolean result. Common comparison operators include "==" for equality, "===" for strict equality, "!=" for inequality, ">" for greater than, "<" for less than, ">=" for greater than or equal to, and "<=" for less than or equal to. These operators are essential for making decisions and controlling the flow of a program.
4 Key excerpts on "Javascript Comparison Operators"
eBook - ePub- Mike McGrath(Author)
- 2020(Publication Date)
- In Easy Steps Limited(Publisher)
...+ sum) sum = 8 ; sum *= 4 console.log(‘ Multiply & assign integer: ‘ + sum) sum = 8 ; sum /= 4 console.log(‘ Divide & assign integer: ‘ + sum) sum = 8 ; sum %= 4 console.log(‘ Modulus & assign integer: ‘ + sum) Save the HTML document, then open it in your browser and launch the console to see the assigned values Make Comparisons The operators that are commonly used in JavaScript to compare two values are all listed in the table below: Operator Comparison === Equality !== Inequality > Greater than < Less than >= Greater than or equal to <= Less than or equal to The === equality operator compares two operands and will return a. Boolean true value if they are exactly equal, otherwise it will return a Boolean false value. If the operands are identical numbers they are equal; if the operands are strings containing the same characters in the same positions they are equal; if the operands are Boolean values that are both true, or both false, they are equal. Conversely, the !== inequality operator returns true if the two operands are not equal, using the same rules as the === equality operator. Equality and inequality operators are useful in comparing two values to perform “conditional branching”, where the script will follow a particular direction according to the result. The > greater than operator compares two operands and returns true if the first is greater in value than the second. The < less than operator makes the same comparison but returns true when the first is less in value than the second...
eBook - ePubConfident Web Design
Master the Fundamentals of Website Creation and Supercharge Your Career
- Kenny Wood(Author)
- 2018(Publication Date)
- Kogan Page(Publisher)
...Conversely, anything without a value will return false. Some examples of things that return false are:The Number 0 (0 and –0).Empty Strings (“”).Undefined variables (var x;).The value null (var x = null).False values (var x = false).NaN not a number variable (var x = “Hi” / 20).Because everything in JavaScript is either true or false, it allows us to use anything as a condition for a condition statement. This brings us nicely on to the topic of comparisons.ComparisonsComparisons in JavaScript are exactly as their name implies – they are ways of analysing and comparing different things in JavaScript to determine equality or difference in the statement. If something is ‘correct’ it is true; if incorrect, it’s false.Let’s compare some statements against a variable we will now define with a value of 10:1 < 10 || 5 > 10This example will return TRUE as one of the conditions is met (1 is less than 10). Remember the above statement can be read as such: ‘if 1 is less than 10 or 5 is greater than 10 then return TRUE.’ This allows us to write more flexible queries that apply to more use-cases, making them more reusable, and thus helping us to write fewer lines of code.All this is great and everything, but you’re probably wondering how we actually use these comparison operators. Well, we can make use of them in conditional statements. What’s a conditional statement? It’s only one of the most important aspects of all programming languages …Conditional statementsConditional statements allow us to write code that gets executed when certain conditions are met. They enable us to write code that reacts and responds to changes and is dynamic in nature. We are able to do this through the use of four different conditional statements. This is another area of JavaScript where it’s much easier to see it in action, rather than explain...
- Kenneth J. Luterbach(Author)
- 2018(Publication Date)
- Routledge(Publisher)
...In the Pascal programming language,:= is the assignment operator, rather than = precisely to avoid the potential for false interpretations of an assignment statement as an expressions of equality. In JavaScript, as well as many other procedural programming languages, the equal sign is the assignment operator. When encountering assignment statements in JavaScript (and other programming languages), you may say “becomes” when you encounter an equal sign in an assignment statement. numberOfQuestions = numberOfQuestions + 1; The value of the variable numberOfQuestions becomes the current value of numberOfQuestions plus one. You may prefer this succinct version: numberOfQuestions becomes numberOfQuestions plus one. Conditional Statements A conditional statement tests a Boolean expression and then, based on whether that expression is true or false, branches to a particular set of statements to execute. For ease of reading (and debugging) source code, the true task and false tasks of an if statement are indented, as shown below. The true task is the set of statements executed when the Boolean expression is true whereas the false task is the set of statements executed when the Boolean expression is false. In the example below, if the value of sum is 14 when program execution encounters the if statement "The sum is 14." is displayed. In contrast, if the value of sum is any number other than 14, the false task executes, which displays, "The sum is not 14." if(sum == 14){ //true task print("The sum is 14."); } else{ //false task print("The sum is not 14."); } In JavaScript, the comparison operator for equality is ==. This bears repeating! Always recall that in JavaScript, the equal sign (=) is the assignment operator; == is the equality comparison operator...
eBook - ePub- Marcus Geduld(Author)
- 2013(Publication Date)
- Routledge(Publisher)
...Those sure look like index numbers. Actually, there’s no contradiction. In JavaScript, arrays are special types of objects. Whereas most objects have properties and methods, array objects have properties, methods, and index numbers. By the way, when we access myArray.length, we’re accessing the length property of the myArray object. Math is an object. When I want to round down, I call its floor method, as in Math.floor(17.23). In doggy JavaScript, we might access a breed property, as in Rover.breed. Or we might call a fetch method, as in Rover.fetch(“stick”). JavaScript also lets you store objects in variables; for example, var myComp = thisComp; You can also use variables to store properties and the values spit out by methods. In Chapter05.aep, Comp4, on the only layer’s Opacity property, I’ve typed this silly Expression: var myComp = thisComp; var myLayer = myComp.layer(“clover”); var myGroup = myLayer.transform; var myProperty= myGroup.rotation; myProperty That Expression does the same thing as thisComp.layer(“clover”). transform.rotation Operators Operators are little “machines” that alter or compare values. The ones you know best are the arithmetic operators: +, −, *, and /. Those are called, respectively, the addition operator, the subtraction operator, the multiplication operator, and the division operator. The values they operate on are called operands. For instance, in the statement var myAge = 40 + 3; + is the operator; 40 and 3 are the operands. Here are a few lesser-known but important operators: + =, − =, * =, and / =. + = is just a shorthand for adding two numbers together...
