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 ...
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读牛人技术博...
oBtn.onclick=function(){//读取的是行间样式中的display属性,由于行间样式没有写,第一次默认值为空,空等于“none”if(oDiv.style.display=="block"||oDiv.style.display==""){ oDiv.style.display='none'; }else{ oDiv.style.display="block"} } }.box{width:200px;height:400px;background-color:gold...
代码中的condition用来表示if后面的条件表达式,consequence 表示如果if条件成立的话所要执行的语句集合,alternative用来表示else部分的语句集合。BlockStatement类用来表示ifelse语句中第一个大括号内或接着else部分的大括号内所要执行的所有语句的集合 接着我们要添加对应的解析函数的实现,继续添加如下代码: 代码语言:javasc...
So what's else used for? The else statement executes a piece of code if the condition in the preceding if statement isn't met. In other words, if the condition mentioned in an if statement evaluates down to false, the corresponding else block takes over. Together, the if and else statem...
// 1.双分支if(表达式1) { 代码块1; }else{ 代码块2; }// 2.多分支if(表达式1) { }elseif(表达式2) { } ...elseif(表达式2) { }else{ } if 嵌套 if(表达式1) {if(表达式2) { }... }... 2、switch语句 switch(表达式) {case值1: 代码块1;break;case值2: 代码块2;break;default:...
In JavaScript we have the following conditional statements:Use if to specify a block of code to be executed, if a specified condition is true Use else to specify a block of code to be executed, if the same condition is false Use else if to specify a new condition to test, if the ...
for different decisions. if else Statements < If the condition is true one block of statements ( if) is executed, else blockis executed. if (condition) { code to be executed; //if condition is true } else { code to ...
JavaScript if...else StatementIn computer programming, the if...else statement is a conditional statement that executes a block of code only when a specific condition is met. For example,Suppose we need to assign different grades to students based on their scores....
Logical NOT (!) - JavaScript | MDN (mozilla.org) How to negate code in "if" statement block in JavaScript -JQuery like 'if not then..' Olorunfemi Akinlua He is boasting over five years of experience in JavaScript, specializing in technical content writing and UX design. With a keen foc...