Javascript 如何通过输入值检查数组值?
我想编写一个程序,它可以从用户输入的字符串中读取值,并可以验证该字符串是否匹配任何数组。如果匹配,则程序将在HTML标记中返回该字符串 我声明了一个名为cars的数组,并通过它创建了一个循环来检查数组的每个值。每次我得到的字符串不可用Javascript 如何通过输入值检查数组值?,javascript,html,arrays,input,Javascript,Html,Arrays,Input,我想编写一个程序,它可以从用户输入的字符串中读取值,并可以验证该字符串是否匹配任何数组。如果匹配,则程序将在HTML标记中返回该字符串 我声明了一个名为cars的数组,并通过它创建了一个循环来检查数组的每个值。每次我得到的字符串不可用 <html> <head> <title>Check Whether it is present or not</title> <meta charset="utf-8"
<html>
<head>
<title>Check Whether it is present or not</title>
<meta charset="utf-8">
<link rel="stylesheet" href="Design.css" />
</head>
<body>
<div>
<input type="text" id="txt">
<input type="button" value="Check" id="btn">
</div>
<div>
<p id="para">para</p>
</div>
<script src="Soul.js"></script>
</body>
</html>
function check() {
let intText = document.getElementById("txt").value;
let cars = ["Lamborghini", "BMW", "Ferrari"];
for (let i = 0; i < cars.length; i++) {
if (intText == cars[i]) {
return document.getElementById("para").innerHTML = cars[i] + " is present";
}
else {
return document.getElementById("para").innerHTML = "Not Available";
}
}
return cars;
}
btn.addEventListener('click', check, false);
如果用户输入BMW,则必须返回BMW是否存在
同样,兰博基尼必须返回兰博基尼在场
但是
Bugatti必须返回Not Present只需使用include在数组中查找匹配项即可。不需要for循环
cars.includes(intText)
let intText = document.getElementById("txt").value;
let cars = ["Lamborghini", "BMW", "Ferrari"];
功能检查{
让intText=document.getElementByIdtxt.value;
let cars=[兰博基尼、宝马、法拉利];
ifcars.includesintText{
return document.getElementByIdpara.innerHTML=intText+存在;
}
否则{
return document.getElementByIdpara.innerHTML=不可用
}
}
btn.addEventListener'click',check,false;
检查它是否存在
para
您可以通过以下简单条件实现: var输入=BMW; var输入2=标致 功能检查车{ var汽车=[宝马、兰博、布加迪]; 如果!!~cars.indexOfcar{ 返回车+存在; } 还车+不存在; } console.logcheckCarinput;
console.logcheckCarinput2 除非需要,否则不要使用循环
function check() {
let intText = document.getElementById("txt").value;
let cars = ["Lamborghini", "BMW", "Ferrari"];
if(cars.includes(intText)){
document.getElementById("para").innerHTML =intText + " is present";
} else {
document.getElementById("para").innerHTML = "Not Available";
}
}
btn.addEventListener('click', check, false);
匹配时应断开循环。
功能检查{
document.getElementByIdpara.innerHTML=;
让intText=document.getElementByIdtxt.value;
let cars=[兰博基尼、宝马、法拉利];
var标志=cars.indexofintext;
如果存在标志>-1return document.getElementByIdpara.innerHTML=intText+;
else return document.getElementByIdpara.innerHTML=不可用;
}
btn.addEventListener'click',check,false;
检查它是否存在
功能检查{ 让intText=document.getElementByIdtxt.value; let cars=[兰博基尼、宝马、法拉利]; 如果cars.indexofintext!=-1{ return document.getElementByIdpara.innerHTML=intText+存在; }否则{ return document.getElementByIdpara.innerHTML=不可用; } 返回车辆; } btn.addEventListener'click',check,false; 检查它是否存在
在数组值的情况下使用indexOf,而不是使用==条件 <head>
<title>Check Whether it is present or not</title>
<meta charset="utf-8">
<link rel="stylesheet" href="Design.css" />
</head>
<body>
<div>
<input type="text" id="txt">
<input type="button" value="Check" id="btn">
</div>
<div>
<p id="para">para</p>
</div>
<script src="Soul.js"></script>
</body>
</html>
<html>
<head>
<title>Check Whether it is present or not</title>
<meta charset="utf-8">
<link rel="stylesheet" href="Design.css" />
</head>
<body>
<div>
<input type="text" id="txt">
<input type="button" value="Check" id="btn">
</div>
<div>
<p id="para">para</p>
</div>
<script src="Soul.js"></script>
</body>
</html>
<script>
function check() {
let intText = document.getElementById("txt").value;
let btn = document.getElementById("btn");
let cars = ["Lamborghini", "BMW", "Ferrari"];
let text = "Not Available";
for (let i = 0; i < cars.length; i++) {
let car = cars[i];
if (intText == car) {
text = car;
break;
}
}
document.getElementById("para").innerHTML = text + " is present";
}
btn.addEventListener('click', check, false);
</script>