JS或jQuery如何删除键值对

Question

Using JS or jQuery how to delete the key-value pair which the value is of type “ Null ” & "" . eg before:

Object {style: "fruit", origin: "Thailand", day: "18d", color: "", weight: null}

alter:

Object {style: "fruit", origin: "Thailand", day: "18d"}

Answer 1

There are two parts to this:

1. Loop through the object's properties

2. Remove a property from an object

There are lots of ways to do the first, covered by this question's answers . Assuming you only care about "own" (non-inherited) properties, I'd probably use Object.keys to get an array of property names and then loop that.

The second is done with the delete operator.

So:

Object.keys(theObject).forEach(function(key) {
    var value = theObject[key];
    if (value === "" || value === null) {
        delete theObject[key];
    }
});

Live Example:

 var theObject = { style: "fruit", origin: "Thailand", day: "18d", color: "", weight: null }; console.log("Before:", JSON.stringify(theObject, null, 2)); Object.keys(theObject).forEach(function(key) { var value = theObject[key]; if (value === "" || value === null) { delete theObject[key]; } }); console.log("After:", JSON.stringify(theObject, null, 2)); 

Answer 2

You can use for..in to go through the loop to find which key has null or "" .

Then use delete to delete the key

var myObj = {
  style: "fruit",
  origin: "Thailand",
  day: "18d",
  color: "",
  weight: null
}

for(var keys in myObj){
 if(myObj[keys] ===null || myObj[keys] === ""){
  delete myObj[keys]
 }
}
console.log(myObj)

JSFIDDLE

Answer 3

An easy solution by iterating threw the keys of your object and pushing properties matching in a resulting Array :

var input = {style: "fruit", origin: "Thailand", day: "18d", color: "", weight: null};
var keys = Object.keys(input);
var result = {};
keys.forEach(key => {if (input[key] != null && input[key] != "") result[key] = input[key]});
console.log(result); // { style: 'fruit', origin: 'Thailand', day: '18d' }

Answer 4

var yourObj={style: "fruit", origin: "Thailand", day: "18d", color: "", weight: null}

for(var attr in yourObj){
  if(!yourObj[attr]){
    delete yourObj[attr]
  }
}

Answer 5

It can be done using this code :

var map = {style: "fruit", origin: "Thailand", day: "18d", color: "", weight: null};

for (var i in map){
    if(map[i]==null || map[i]==""){
       delete(map[i]);
 }
}