printVegetablesWithQuantity('cabbage');// We have 1 cabbage! printVegetablesWithQuantity('potato',2);// We have 2 potato! 如果vegetable 是一个对象呢?我们能赋一个默认参数吗? functionprintVegetableName(vegetable){ if(vegetable && vegetable.name) { console.log (vegetable.name); }else{ console....
We can omit { } in if…else statements when we have a single line of code to execute. For example, let num = 4; // if condition if (num % 2 == 0) console.log("even number"); else console.log("odd number"); // Output: even number Run Code JavaScript...
JavaScript includes three forms of if condition: if condition, if else condition and else if condition. The if condition must have conditional expression in brackets () followed by single statement or code block wrapped with. 'else if' statement must be placed after if condition. It can be us...
在 JavaScript 文件中，我们可以使用各种方式来初始化数据项，例如从服务器获取数据、从本地缓存获取数据、从用户输入获取数据等等。通过使用 wx:if 和 wx:else 标签，我们可以方便地实现条件判断的 else 分支，从而增强小程序的可用性和交互性。3、wx:for 循环 WXML 模板中，可以使用 wx:for 列表渲染标签，实现...
JavaScript var isRaining = false; if (isRaining) { alert("Don't forget an umbrella!"); } else { alert("No need for an umbrella."); } Live Example The moment we run the code, we get the second alert, just as we expected. Also notice the body of else. Just like that of if,...
JavaScript If Else If statement The If Else If statement is more powerful than the previous two. This is because you can specify many different outputs based on many different conditions — all within the one statement. You can also end with an else to specify what to do if none of the ...
但是如果情况太多,就会出现一大堆的“if else”,这就是为什么很多遗留系统中,一个函数可能出现上千行的代码。...短信渠道一般配置在文件中,或者配置在数据库中。...//从配置中读取 短信渠道 String channelType=config.getChannelType(); //如果是短信渠道A,则调用渠道
1. if语句基础 Python语言的ifi语句有如下3种形式。 第1种形式: 代码语言:javascript 复制 ifexpression:statements... 第2种形式: 代码语言:javascript 复制 ifexpression:statements...else:statements... 第3种形式: 代码语言:javascript 复制 ifexpression:statements ...
1. That else if{} not if else{} 2. remove semicolons on the end of if line var height = parseFloat(readLine(), 10) //your goes code here if (height >= 2.45) { console.log ("new record!"); } else if (height >= 2.44) { console.log ('not this time!'); } 23rd Sep 202...
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