如何使用js查找数组中符合条件的元素

let arr = [
  {name: 'zhangsan', age: 18},
  {name: 'lisi', age: 17},
  {name: 'xiaoming', age: 18},
],
result = []
for (let item of arr){
  if(item.age === 18){
    result.push(item);
  }
}
console.log(result);// [{name: 'zhangsan', age: 18},{name: 'xiaoming', age: 18}]

let arr = [
  {name: 'zhangsan', age: 18},
  {name: 'lisi', age: 17},
  {name: 'xiaoming', age: 18},
];
let result = arr.filter(item=>item.age === 18)
console.log(result);// [{name: 'zhangsan', age: 18},{name: 'xiaoming', age: 18}]

let arr = [
  {name: 'zhangsan', age: 18},
  {name: 'lisi', age: 17},
  {name: 'xiaoming', age: 18},
];
let result = arr.find(item=>item.age === 18)
console.log(result);// {name: 'zhangsan', age: 18}

var newArray  = {};//新对象
var array = [
 {name:'aiai',age:18},
 {name:'sisi',age:18},
 {name:'lulu',age:18},
 {name:'sisi',age:19}
]; 
//查找符合条件值并存入新数组
newArrar = this.array.find((item) => {
   if(item.name === 'sisi'){
     return item
   }
 })
//此时 newArray = {name:'sisi',age:18}

var newArray  = [];//新数组
var j = 0;
var array = [
 {name:'aiai',age:18},
 {name:'sisi',age:18},
 {name:'lulu',age:18},
 {name:'sisi',age:19}
]; //目标数组
 
//查找符合条件值并存入新数组
for(let i in array){
 if(array[i].name == 'sisi'){
  newArray[j++] = array[i]
 }
}
//此时 newArray = [{name:'sisi',age:18},{name:'sisi',age:19}]