Remove json element

var json = { ... };
var key = "foo";
delete json[key]; // Removes json.foo from the dictionary.

You can use splice to remove elements from an array.


You can try to delete the JSON as follows: 

var bleh = {first: '1', second: '2', third:'3'}

alert(bleh.first);

delete bleh.first;

alert(bleh.first);

Alternatively, you can also pass in the index to delete an attribute: 

delete bleh[1];

However, to understand some of the repercussions of using deletes, have a look here


For those of you who came here looking for how to remove an object from an array based on object value:

let users = [{name: "Ben"},{name: "Tim"},{name: "Harry"}];

let usersWithoutTim = users.filter(user => user.name !== "Tim");

// The old fashioned way:

for (let [i, user] of users.entries()) {
  if (user.name === "Tim") {
    users.splice(i, 1); // Tim is now removed from "users"
  }
}

Note: These functions will remove all users named Tim from the array.


Do NOT have trailing commas in your OBJECT (JSON is a string notation)

UPDATE: you need to use array.splice and not delete if you want to remove items from the array in the object. Alternatively filter the array for undefined after removing

var data = {
  "result": [{
    "FirstName": "Test1",
    "LastName": "User"
  }, {
    "FirstName": "user",
    "LastName": "user"
  }]
}
console.log(data.result);
console.log("------------ deleting -------------");
delete data.result[1];
console.log(data.result); // note the "undefined" in the array.


data = {
  "result": [{
    "FirstName": "Test1",
    "LastName": "User"
  }, {
    "FirstName": "user",
    "LastName": "user"
  }]
}

console.log(data.result);
console.log("------------ slicing -------------");
var deletedItem = data.result.splice(1,1);
console.log(data.result); // here no problem with undefined.

Tags:

Javascript

Json

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