I want to delete objects that do not have a specific array-CodePudding

console.log(value)

{
    List: [
        {
            id: 1
            title: 'hi',
            content: [
                {
                    id: 1,
                    functionId: 11,
                }
            ]
        }
        {
            id: 2,
            title: 'minsu',
            content: []
        }
    ]
}

I want to delete the object if there is no content array.

I am creating a variable called control and outputting it using the map function inside. If the objects without content array have to be deleted by applying a filter condition, I don't know how to do it.

let control: any[any] = [
    value.map((value: any) => {
        return {
            id: value?.id,
            title: value?.title,
            content: value?.content[0].functionId
        }
    })
]

But now, when I do console.log(control), an error occurs because the second object does not have content.

I want to delete the second object without content and print it like this.

console.log(control) 
[
    id: 1,
    title: 'hi',
    functionId: 11
]

CodePudding user response：

First filter out the elements with 0 length content array or content array doesn't exists and then map to transform it

const List  = [        {            id: 1,            title: 'hi',            content: [                {                    id: 1,                    functionId: 11,                }            ]        },        {            id: 2,            title: 'minsu',            content: []        }    ]

const control = List
.filter(({content}) => content?.length)
.map(({id,title,content:[{functionId}]}) => ({id,title,functionId}))

console.log(control)

CodePudding user response：

Filter source list the way you need and reapply filtered list as new value

const sourceObject = {
    list: [
        {
            id: 1,
            title: 'hi',
            content: [
                {
                    id: 1,
                    functionId: 11,
                }
            ]
        },
        {
            id: 2,
            title: 'minsu',
            content: []
        }
    ]
};

const filteredList = sourceObject.list.filter(element => (
  typeof(element.content) === 'object' && element.content.length > 0
));

sourceObject.list = filteredList;

console.log(sourceObject);

CodePudding user response：

I usually use reduce to solve problems like this

const items = [
  {
    id: 1,
    title: 'hi',
    content: [
      {
        id: 1,
        functionId: 11,
      }
    ]
  },
  {
    id: 2,
    title: 'minsu',
    content: []
  }
];

const result = items.reduce((rs, item) => {
  const functionId = item?.content?.[0]?.functionId;
  if (functionId) {
    rs.push({
      id: item.id,
      title: item.title,
      functionId
    })
  }
  return rs;
}, [])


console.log(result)