* 計算對象數(shù)組中每個電腦操作系統(tǒng)是否可用
 * 大于16位操作系統(tǒng)表示可用,否則不可用
*/

var computers = [
  {name:"Apple",ram:16},
  {name:"IBM",ram:4},
  {name:"Acer",ram:32}
];

var everyComputersCanRunProgram = true;
var someComputersCanRunProgram = false;

for(var i = 0; i < computers.length; i++){
  var computer = computers[i];
  if(computer.ram < 16){
    everyComputersCanRunProgram = false;
  }else{
    someComputersCanRunProgram = true;
  }
}

console.log(everyComputersCanRunProgram);
console.log(someComputersCanRunProgram);

/** 
 * Every: 一真即真
 * Some: 一假即假
 */

 var every = computers.every(function(computer){
   return computer.ram > 16;
 })

 console.log("==========");
 console.log(every);

 var some = computers.some(function(computer){
  return computer.ram > 16;
 })

 console.log(some);


/** 場景2
 * 假定有一個注冊頁面,判斷所有input內(nèi)容的長度是否大于0 
 * 
 */
 console.log("================");

 function Field(value){
   this.value = value;
 }

 Field.prototype.validate = function(){
   return this.value.length > 0;
 }

 var username = new Field("henrywu");
 var telephone = new Field("18888888888");
 var password = new Field("my_password");

//  console.log(username.validate());
//  console.log(telephone.validate());
//  console.log(password.validate());

 var fields = [username,telephone,password];

 var formIsValid = fields.every(function(field){
  return field.validate();
 })

 console.log(formIsValid);

 if(formIsValid){
  // 注冊成功
 }else{
   // 給用戶一個友善的錯誤提醒
 }