如何检查json数组中是否存在值javascript

Question

I have the following Structure:

_id: 'blog',
    posts: [
      {
        _id: 'politics and economy',
        name: 'politics and economy',
        author: 'Mark',
      },
      {
        _id: 'random',
        name: 'random',
        author: 'Michael'
      }
    ]

My if Statement :

if(posts.name.includes("politics"){
//Doing Stuff
}

How Can I get this running? I do not know the length of the Array.

Answer 1

No need to know the length, you can use forEach

posts.forEach(post => {
    if(post.name.includes("politics")){
        //Doing Stuff
    }
});

Answer 2

You can use the method some to check if one of the posts has the value

var name = "politics";
posts.some(singlePost => {
     return singlePost.name == name;
});

Answer 3

Use the array filter method. Link

Answer 4

if(posts.filter(post => post.name.includes("politics")).length > 0){
//Doing Stuff
console.log("One of posts has a name including politics")
}
 

Answer 5

 const posts = [ { _id: 'politics and economy', name: 'politics and economy', author: 'Mark' }, { _id: 'random', name: 'random', author: 'Michael' } ] posts.forEach(post => { if(post.name.includes("politics")){ //Do Your Stuff console.log(post.name) } });

You have to loop through the posts array.