根据以下数据，我们想用西瓜替换summerFruits列表中的浆果。

const summerFruits = [
{id:1,name:'apple'}, 
{id:2, name:'orange'}, 
{id:3, name: 'berries'}];

const fruit = {id:3, name: 'watermelon'};

有两种方法。

第一种方法:

//create a copy of summer fruits.
const summerFruitsCopy = [...summerFruits];

//find index of item to be replaced
const targetIndex = summerFruits.findIndex(f=>f.id===3); 

//replace the object with a new one.
summerFruitsCopy[targetIndex] = fruit;

第二种方法:使用map和spread:

const summerFruitsCopy = summerFruits.map(fruitItem => 
fruitItem .id === fruit.id ? 
    {...summerFruits, ...fruit} : fruitItem );

summerFruitsCopy列表现在将返回一个更新对象的数组。

这里我使用的是angular js。在javascript中，你可以使用for循环来查找。

    if($scope.bechval>0 &&$scope.bechval!=undefined)
    {

                angular.forEach($scope.model.benhmarkghamlest, function (val, key) {
                $scope.model.benhmarkghamlest[key].bechval = $scope.bechval;

            });
    }
    else {
        alert("Please sepecify Bechmark value");
    }

你必须像这样在数组中搜索:

function changeDesc( value, desc ) {
   for (var i in projects) {
     if (projects[i].value == value) {
        projects[i].desc = desc;
        break; //Stop this loop, we found it!
     }
   }
}

然后像这样使用它

var projects = [ ... ];
changeDesc ( 'jquery-ui', 'new description' );

更新:

为了更快:

var projects = {
   jqueryUi : {
      value:  'lol1',
      desc:   'lol2'
   }
};

projects.jqueryUi.desc = 'new string';

(根据Frédéric的评论，你不应该在对象键中使用连字符，或者你应该使用“jquery-ui”和项目["jquery-ui"]符号。)

您需要知道要更改的对象的索引。这很简单

projects[1].desc= "new string";

用每个循环使用的条件更改值

projects.forEach((p,index)=>{
    if(index === 1){
       p.value = "Updated jquery-ui"
    }
})

// using higher-order functions to avoiding mutation var projects = [ { value: "jquery", label: "jQuery", desc: "the write less, do more, JavaScript library", icon: "jquery_32x32.png" }, { value: "jquery-ui", label: "jQuery UI", desc: "the official user interface library for jQuery", icon: "jqueryui_32x32.png" }, { value: "sizzlejs", label: "Sizzle JS", desc: "a pure-JavaScript CSS selector engine", icon: "sizzlejs_32x32.png" } ]; // using higher-order functions to avoiding mutation index = projects.findIndex(x => x.value === 'jquery-ui'); [... projects.slice(0,index), {'x': 'xxxx'}, ...projects.slice(index + 1, projects.length)];