The if/else statement is a part of JavaScript's "Conditional" Statements, which are used to perform different actions based on different conditions. In JavaScript we have the following conditional statements: Useifto specify a block of code to be executed, if a specified condition is true ...
if( condition )statement_1statement_2; 如果不使用花括号,将很难看出 statement_2 不属于 if 块。 如果您想在条件计算结果为 false 时执行另一条语句,请按如下方式使用 else: if( condition ) {//statement}else{//statement (...
if (condition) statement1 else statement2 1. 其中condition可以是任何表达式,计算的结果甚至不必是真正的 boolean 值,ECMAScript 会把它转换成 boolean 值。 如果条件计算结果为 true,则执行statement1;如果条件计算结果为 false,则执行statement2。 每个语句都可以是单行代码,也可以是代码块。 还可以串联多个 if ...
The else StatementUse the else statement to specify a block of code to be executed if the condition is false.if (condition) { block of code to be executed if the condition is true } else { block of code to be executed if the condition is false }...
JavaScript if else 语句简介 if 语句可能是 JavaScript 中最常用的语句之一。if 语句在满足条件时执行语句或代码块。下面是 if 语句的简单形式: if( condition ) statement; 1. 2. 条件可以是任何有效的表达式。通常,条件计算为布尔值,真值或假值。
To write this set of code we need to write a compound if else statement using Boolean logic to test if both conditions are true. How to use AND, OR in the JavaScript IF statement As mentioned above, the condition for the if statement need not be a single variable but can consist of ...
The else statement is another conditional statement in JavaScript. Unlike if, it couldn't be specified alone — there has to be an if statement preceding an else. So what's else used for? The else statement executes a piece of code if the condition in the preceding if statement isn't me...
if...else if...else 语句- 使用该语句来选择多个代码块之一来执行 switch 语句- 使用该语句来选择多个代码块之一来执行 If 语句 只有当指定条件为 true 时,该语句才会执行代码。 语法 if (条件) { 只有当条件为 true 时执行的代码 } 注意:请使用小写的 if。使用大写字母(IF)会生成 JavaScript 错误! 实例...
问我的"If Else语句“在JavaScript中不起作用(尝试执行等式，如果值为false，则警告用户)EN读牛人技术...
JavaScript Author:Olorunfemi Akinlua Reviewer:Deepak Prasad Introduction There are different ways to phrase conditional logic. If we have a certain condition, let’s do this, else, let’s do that. This is the typical logic that guides conditional logic, and basically theif/elsestatement. However...