我想循环数组，并使我的循环返回函数，如果名称不存在？

Question

我想在数组上循环，并使我的循环返回函数或一个时间字符串表示名称存在？这是错误类型错误：无法读取未定义的var x=arr[i]的属性“name”。.name；

var arr = [
  {id: 1, name: "php"},
  {id: 2, name: "mysql"},
  {id: 3, name: "laravel"},
  {id: 4, name: "codeigniter"},
  {id: 5, name: "wordpress"},
  {id: 6, name: "sql"},
  {id: 7, name: "jquery"},
  {id: 8, name: "javascript"},
];

var string;

function checkemail(arr, string) {
  var i;

  for (i = 0; i < arr.length; i++) {
    let newname = arr[i].name;

    if (newname !== string) {
      return storename();
    } else {
      console.log("name found")
    }
  }
}
}

console.log(checkemail(arr, "javascript"));

Answer 1

在决定数组中元素的存在性之前，应该遍历整个数组

当名称和参数第一次不匹配时，您正在调用storename函数。这将使函数检查第一个元素，并在调用storename函数后返回。

我的实现

function storename() {
  return 'storename function';
}
var arr = [
  { id: 1, name: "php" },
  { id: 2, name: "mysql" },
  { id: 3, name: "laravel" },
  { id: 4, name: "codeigniter" },
  { id: 5, name: "wordpress" },
  { id: 6, name: "sql" },
  { id: 7, name: "jquery" },
  { id: 8, name: "javascript" },
];

var string;

function checkemail(arr, string) {
  var i;
  let isFound = false;
  for (i = 0; i < arr.length; i++) {
    let newname = arr[i].name;
    if (newname === string) {
      isFound = true;
      i = arr.length; // Item found, you can exit the loop now
      return "name found";
    }
  }
  if(!isFound) {
    return storename()
  }
}


console.log(checkemail(arr, "javascript"));