使用for of循环和if..else语句迭代和检查数组

Question

我正在尝试创建一个带有名称的数组，然后使用for of循环迭代它们，然后使用if else语句检查迭代。我的代码在下面，但是它没有工作，我没有看到结果。我试过了，同样糟糕的结果。在Html文件中，我有一个带演示id的副部曲和一个具有迭代和检查数组功能的按钮。

function availableName() {

 const check = document.getElementById('userID');
 const takenNames=['manuel','remus','manuel-remus','tomi','mirel'];
 const reservedNames=['cristina','angela','rusanda','costantin'];
 const givenNames=[...takenNames, ...reservedNames];

  for (givenName of givenNames) {
  if (givenName === check) {
      sayMessage=givenName +"Not available!";
 }
 else {
   sayMessage= givenName +"Available";
 }

 }
document.getElementById("available").innerHTML= sayMessage;
 };

Answer 1

首先，您需要使用input获得.value的值，如注释中所述。

然后，要检查它在array中的存在，可以使用Array的内置方法之一，比如includes()或indexOf()。

这应该是您的代码：

function availableName() {
  const check = document.getElementById('userID').value;
  const takenNames = ['manuel', 'remus', 'manuel-remus', 'tomi', 'mirel'];
  const reservedNames = ['cristina', 'angela', 'rusanda', 'costantin'];
  const givenNames = [...takenNames, ...reservedNames];

  if (givenNames.indexOf(check) > 0) {
    sayMessage = check + " Not available!";
  } else {
    sayMessage = check + " Available";
  }
  document.getElementById("available").innerHTML = sayMessage;
};

演示：

这是一个演示：

​

function availableName() {
  //const check = document.getElementById('userID').value;
  const check = "cristina";
  const takenNames = ['manuel', 'remus', 'manuel-remus', 'tomi', 'mirel'];
  const reservedNames = ['cristina', 'angela', 'rusanda', 'costantin'];
  const givenNames = [...takenNames, ...reservedNames];

  if (givenNames.indexOf(check) > 0) {
    sayMessage = check + " Not available!";
  } else {
    sayMessage = check + " Available";
  }
  document.getElementById("available").innerHTML = sayMessage;
};

availableName();

<div id="available"></div>

​

Answer 2

为什么不使用函数isInArray？

function isInArray(value, array) {
    return array.indexOf(value) > -1;
}

function availableName() {
const check = document.getElementById('userID');
 const takenNames=['manuel','remus','manuel-remus','tomi','mirel'];
 const reservedNames=['cristina','angela','rusanda','costantin'];
 const givenNames=[...takenNames, ...reservedNames];
for (givenName of givenNames) {
  if (isInArray(check, givenNames)) {
      sayMessage=givenName +"Not available!";
 }
 else {
   sayMessage= givenName +"Available";
 }

 }
document.getElementById("available").innerHTML= sayMessage;
 };