如何检查相同的 属性 存在于单个对象数组 javascript 中

How to check same property exists in single array of object javascript

我想知道对象数组在 javascript

中是否具有相同的 属性 值

为数组对象list1,

if name and country has same value, return true

if name same, any object country has value SG return true

if above two conditions fails, return false

var list1=[
  {id:1, name: "sen", country: "IN"},
  {id:2, name: "sen", country: "IN"}
]
const result1=checkObj(list1);

var list2=[
  {id:1, name: "sen", country: "IN"},
  {id:2, name: "sen", country: "SG"}
]
const result2=checkObj(list2);

var list3=[
  {id:1, name: "sen", country: "IN"},
  {id:2, name: "sen", country: "TH"}
]
const result3=checkObj(list3);
Expected Result:
//when passing list1
true
//when passing list2
true
//when passing list3
false

试试这个,

var list1=[
  {id:1, name: "sen", country: "IN"},
  {id:2, name: "sen", country: "IN"}
]
const result1=checkObj(list1);

console.log(result1);

var list2=[
  {id:1, name: "sen", country: "IN"},
  {id:2, name: "sen", country: "SG"}
]
const result2=checkObj(list2);

console.log(result2);

var list3=[
  {id:1, name: "sen", country: "IN"},
  {id:2, name: "sen", country: "TH"}
]
const result3=checkObj(list3);

console.log(result3);

function checkObj(list){
  for(i=0;i<list.length;i++)
  {  
   for(j=0;j<list.length;j++)
    {
      if(j!=i){
        if(list[i].name==list[j].name){
          if(list[i].country==list[j].country || list[i].country =='SG'){
          return true;
          }
        }
      }
    }
  }
  return false;
}

在下面的代码片段中,我汇总了一种基于对数组的所有元素进行单循环的方法。 name/country 组合的出现被收集在本地对象 o 中,并在函数结束时进行检查。

const data=[[
  {id:1, name: "sen", country: "IN"},
  {id:2, name: "sen", country: "IN"}
],[
  {id:1, name: "sen", country: "IN"},
  {id:2, name: "sen", country: "SG"},
  {id:1, name: "sen", country: "DN"},
  {id:1, name: "sen", country: "EN"}
],[
  {id:1, name: "sen", country: "IN"},
  {id:2, name: "sen", country: "TH"}
]];

function dupes(arr){
  const o={}, // object o counts all occurrences
    // the sort makes sure the "SG" items come last in ar
    ar= arr.slice(0).sort((a,b)=>a.country==="SG" ? (b.country==="SG" ? 0 : 1) : -1);
  // a single loop over ar:
  ar.forEach(e=>{
   if(e.country!=="SG"){ // "normal" countries:
    let k=e.name+"|"+e.country;
    o[k]=(o[k]||0)+1
   } else {  // for country=="SG"
    for (let k in o)
     if (k.indexOf(e.name+"|")==0)
       o[k]++ // increase counts for all elements starting with <el.name>|
   }
  });
  return Object.values(o).some(n=>n>1)
   
}

data.forEach(d=>console.log(dupes(d)))