Question

我正在用javascript创建一个switch语句。我想使用&&(AND)和||(OR)条件。我希望var user = prompt接受输入14或13，14km或13km，14 km或13 km（与来自用户的空间）。我想对所有其他案件做同样的事情。

我该怎么做？

var user = prompt("How fast can you run per hour in kilometers (km)?").toUpperCase();

switch(user) {

case '14km':
    if ( 14 || 13 == true) {
    console.log("Woah!, your almost as fast as Usain Bolt!");
                           }
    else {
        console.log("RUN FASTER");
         }
    break;
case '12km':
    if ( 12 || 11 == true) {
    console.log("Your quick, but not as quick as me!");
                           }
    else {
        console.log("TOO SLOW");
         }
    break;
case '10km':
    if ( 10 && 9 )    {
    console.log("Average!");
             }
    break;
case '8km':
    console.log("OK tortoise!");
    break;
case '6km':
    console.log("I think it's better you get some rest");
    break;
default:
    console.log("I didn't understand you? Can you repeat that please");
}

Answer 1

您无法将case或&&语句切换为||语句，但您可以为相同的代码指定多个case语句，如下所示：< / p>

switch(user) {
    case '14km':
    case '13km':
    case '14':
    case '13':
        console.log("Woah!, your almost as fast as Usain Bolt!");
        break;
    case '12km':
    case '11km':
    case '12':
    case '11':
        console.log("Your quick, but not as quick as me!");
        break;
    case '10km':
    case '9km':
    case '10':
    case '9':
        console.log("Average!");
        break;
    case '8km':
    case '8':
        console.log("OK tortoise!");
        break;
    case '6km':
    case '6':
        console.log("I think it's better you get some rest");
        break;
    default:
        console.log("I didn't understand you? Can you repeat that please");
}

Answer 2

您可以使用switch语句代码流尝试一些技巧。

请参阅此小提琴，了解您的问题的示例 https://jsfiddle.net/p51h5y4f/1/

请参阅：

case 14:
case 13:
    console.log("Woah!, your almost as fast as Usain Bolt!");
    break;
case 12:
case 11:
    console.log("Your quick, but not as quick as me!");
    break;

在那里，用户输入一个int到框提示符，如果它是14或13，它会进入第一个响应，等等。

Answer 3

您不能将操作符与switch一起使用。但是，您可以在单个块中评估多个案例。

//Using regular expression extract on number
//So that you don't need to evaluate (14 km/14 KM/14km/14KM/14)
user = user.replace(/[^\d.]/g, '');

//Convert to number
user = parseInt(user , 10);

switch(user) {
    case 14:
    case 13:
        console.log("Woah!, your almost as fast as Usain Bolt!");
        break;
    case 12:
    case 11:
        console.log("Your quick, but not as quick as me!");
        break;
    case 10:
    case 9:
        console.log("Average!");
        break;
    case 8:
        console.log("OK tortoise!");
        break;
    case 6:
        console.log("I think it's better you get some rest");
        break;
    default:
        console.log("I didn't understand you? Can you repeat that please");
}

Answer 4

希望var user = prompt接受输入14或13，或14km或13km，或来自用户的14公里或13公里（带空格）

用户必须在html表单中输入值。然后你得到值

document.getElementById('KM').value

Javascript结合AND＆amp;＆amp;或|| switch语句中的条件

4 个答案: