Question

我正在构建一个javascript函数，该函数接收输入并针对数组中存储的对象检查输入，以查看其是否与任何

相匹配

if else语句不起作用

const accounts = []; //holds all user name and password

function getinput() {
  let pass = document.getElementById("password").value;
  let user = document.getElementById("username").value;

  let newuser = {
    username: user,
    password: pass,
  };

  let match = (toMatch) => toMatch === newuser.username
  if (accounts.some(match) === true) {
    return alert("choose another `username");
  }
  accounts.push(newuser)
  return alert("account created")
};
var clik = document.getElementById("login").addEventListener("click", getinput);

它应该告诉用户用户名是否可用

Answer 1

您的问题的直接答案是：

function getInput() {
    /* store the value of the input */
    var current_userName = document.getElementById("username").value;

    /* check if that value already exists in the accounts Array */
    var matched = accounts.find(account => account.username === current_userName);

    /* conditional for each of the two cases */
    if (!matched) {
        /* code if username is available */
    } else {
        /* code if username is NOT available */
    }
};

document.getElementById("login").addEventListener("click" , getInput);

您的代码中有一些错误，需要修复。

另外，请查看Array.prototype.find()以获取更多信息。

希望这将帮助您朝正确的方向开始。祝你好运！

Answer 2

最后了解我在做什么错，必须指向帐户匹配项以检查对象数组中包含的用户名

const  = [ ]; //holds all user name and password

function getinput() {
  let pass = document.getElementById("password").value;
  let user = document.getElementById("username").value;

  let newuser = {
    username: user,
    password: pass,
  };
//this was where I got it wrong I was doing toMatch === newuser.username which was wrong 

  let match = (toMatch) => toMatch.username === user
  if (accounts.some(match) === true) {
    return alert("choose another username");
  }
  accounts.push(newuser)
  return alert("account created")
};
document.getElementById("login

如何运行检查用户名是否可用的javascript函数

2 个答案: