Javascript Articles - Page 586 of 607

JavaScript has a goto statement, which is a reserved keyword. It isn’t popular since it is not needed in JavaScript. Generally, it isn’t considered a good practice to use a goto statement.Using goto with JavaScript preprocessing is still considered good as shown below −var a = 0; [lbl] beginning: console.log("Demo Text!"); a++; if(i < 424) goto beginning;The above code gets translated like the following −var a = 0; beginning: while(true) {    console.log("Demo Text!");    a++;    if(i < 424) continue beginning;    break; }

To control the flow in JavaScript, use labels. A label can be used with break and continue statement to control the flow more precisely. A label is simply an identifier followed by a colon (:) that is applied to a statement or a block of code. We will see two different examples to understand how to use labels with break and continue.ExampleYou can try to run the following code to use labels to control the flow, with break statement −Live Demo                                     ... Read More

JavaScript goto statement is a reserved keyword. Generally, according to web standards it isn’t considered a good practice to use goto statement.Using goto with JavaScript preprocessing is still considered good as shown below.var a = 0; [lbl] beginning: console.log("Demo Text!"); a++; if(i < 424) goto beginning;The above code gets translated like the following −var a = 0; beginning: while(true) { console.log("Demo Text!"); a++; if(i < 424) continue beginning; break; }

The break statement is used to break a loop and continue executing the code, which is after the loop.ExampleYou can try to run the following code to break a loop in JavaScriptLive Demo                          var text = "";          var i;          for (i = 0; i < 5; i++) {             if (i === 2) {                break;             }             text += "Value: " + i + "";          }          document.getElementById("test").innerHTML = text;           OutputValue: 0 Value: 1

The best way to break from nested loops is to use labels. A label can be used with break and continue to control the flow more precisely. A label is simply an identifier followed by a colon (:) that is applied to a statement or a block of code.ExampleYou can try to run the following code to implement Label with a break statement to break from nested loops −Live Demo                    document.write("Entering the loop! ");          outerloop:  // This is the label name          for (var ... Read More

We use the for...in statement of JavaScript for looping over enumerable properties of an array or object. It is a variety of for loops. Unlike other loop constructs in JavaScript, the for...in loop doesn’t have to bother about the number of iterations. This is because the iteration size is fixed based on the enumerable properties of the object or the number of elements in the array. The "for...in" statement in JavaScript A for...in loop iterates over all the enumerable properties of an object. All the properties that are assigned using a simple assignment operator or by default initializer are considered ... Read More

break statementThe break statement is used to exit a loop early, breaking out of the enclosing curly braces.  The break statement exits out of a loop.  Let’s see an example of break statement in JavaScript. The following example illustrates the use of a break statement with a while loop. Notice how the loop breaks out early once x reaches 5 and reaches to document.write (..) statement just below to the closing curly brace, Example                    var x = 1;          document.write("Entering the loop ");         ... Read More

The subtraction operator is also known as the minus operator. It is a binary operator that means it requires at least two operands to operate on. It will not work with a single operand. Generally, the subtraction operator subtracts or minus the value of the second operand from the first operand and returns the result as it is, that means if the result of two numbers subtraction is negative it will return the negative result, else it will return positive result if that’s positive. In this article, we are going to discuss about the subtraction operator in details and its ... Read More

The Unary Negation Operator first converts the operand into a number, and after that it negates. It operates on a single operand. It returns the negation of the operand. A boolean operand is converted to 0 or 1, and then negation is done. Similarly, a number with a base other than decimal is first converted to base 10, then the negation is computed. Syntax The following syntax will show you how you can use the unary negation operator to negate the value of a number − -x Here unary operator (-) negates x. Let us understand the application of ... Read More

The if...else if... statement is an advanced form of if…else that allows JavaScript to make a correct decision out of several conditions.SyntaxThe syntax of an if-else-if statement is as follows −if (expression 1){    Statement(s) to be executed if expression 1 is true } else if (expression2){    Statement(s) to be executed if expression 2 is true } else if (expression3){    Statement(s) to be executed if expression 3 is true } else{    Statement(s) to be executed if no expression is true }ExampleYou can try to run the following to learn how to work with if…else if statement in ... Read More