how to check if an object is in a lsit javascript code example
Example 1: javascript check if is object
obj = {
"data": 123
}
arr = [
"data",
123
]
function obj_or_arr(val) {
if (typeof val === "object") {
try {
for(x of val)
break;
return "array";
} catch {
return "object";
}
} else return false;
}
console.log(obj_or_arr(obj))
console.log(obj_or_arr(arr))
console.log(obj_or_arr(123))
console.log(obj_or_arr("hello world"))
console.log(obj_or_arr(true))
console.log(obj_or_arr(false))
Example 2: check object in array javascript
var obj = {a: 5};
var array = [obj, "string", 5];
array.indexOf(obj) !== -1
Example 3: react array if id is present do not add element
addPerson = (person) => {
let filteredPerson = this.state.likes.filter(like => like.name !== person.name);
this.setState({
likes: [...filteredPerson, person]
})
}