如果两个值都不存在,我如何推入数组?这是我的数组:

[
    { name: "tom", text: "tasty" },
    { name: "tom", text: "tasty" },
    { name: "tom", text: "tasty" },
    { name: "tom", text: "tasty" },
    { name: "tom", text: "tasty" }
]

如果我试图再次推入数组的名字:“tom”或文本:“tasty”,我不希望发生任何事情…但如果这两个都不存在那么我就输入。push()

我该怎么做呢?


当前回答

我建议你使用Set,

集只允许唯一的条目,这将自动解决您的问题。

集合可以这样声明:

const baz = new Set(["Foo","Bar"])

其他回答

您可以使用foreach检查数组,然后弹出项目,如果它存在,否则添加新的项目…

newItemValue &submitFields是键值对

> //submitFields existing array
>      angular.forEach(submitFields, function(item) {
>                   index++; //newItemValue new key,value to check
>                     if (newItemValue == item.value) {
>                       submitFields.splice(index-1,1);
>                         
>                     } });

                submitFields.push({"field":field,"value":value});

使用数组是很容易做到的。函数findIndex,它以函数作为参数:

var arrayObj = [{name:"bull", text: "sour"},
    { name: "tom", text: "tasty" },
    { name: "tom", text: "tasty" }
]
var index = arrayObj.findIndex(x => x.name=="bob"); 
// here you can check specific property for an object whether it exist in your array or not

index === -1 ? arrayObj.push({your_object}) : console.log("object already exists")
 

你可以用一个自定义方法扩展Array原型:

// check if an element exists in array using a comparer function
// comparer : function(currentElement)
Array.prototype.inArray = function(comparer) { 
    for(var i=0; i < this.length; i++) { 
        if(comparer(this[i])) return true; 
    }
    return false; 
}; 

// adds an element to the array if it does not already exist using a comparer 
// function
Array.prototype.pushIfNotExist = function(element, comparer) { 
    if (!this.inArray(comparer)) {
        this.push(element);
    }
}; 

var array = [{ name: "tom", text: "tasty" }];
var element = { name: "tom", text: "tasty" };
array.pushIfNotExist(element, function(e) { 
    return e.name === element.name && e.text === element.text; 
});

A是你拥有的对象数组

a.findIndex(x => x.property=="WhateverPropertyYouWantToMatch") <0 ? 
a.push(objectYouWantToPush) : console.log("response if object exists");

推送后删除重复项

如果你已经有一个包含重复项的数组,将对象数组转换为字符串数组,然后使用Set()函数消除重复项:

let arr_obj = [
    { name: "tom", text: "tasty" }, 
    { name: "tom", text: "tasty" }
]

let arr_str = arr_obj.map(JSON.stringify)

let arr_unique = [...new Set(arr_str)].map(JSON.parse) 

推前检查

如果你到目前为止没有重复的元素,你想在推入一个新元素之前检查重复:

let arr_obj = [
    { name: "tom", text: "tasty" },
    { name: "tim", text: "tusty" }
]

let new_obj = { name: "tom", text: "tasty" }

let arr_str = arr_obj.map(JSON.stringify)

!arr_str.includes(JSON.stringify(new_obj)) && arr_obj.push(new_obj)