void' is not assignable to parameter of type '(value: User[], index: number) => boolean'

Question

I have a model named User and I have an Observer in my service called getUsers which get a bunch of JSON objects in.

In my component I have the following

@Input() users: User[] = [];

and I and trying to use it like this:

   getUserByLastName(lastName){

        this._searchService.getUsers()
            .filter(users => {
                for(let user of users) {
                    if(user.lastName == lastName){
                        this.users.push(user);
                    }}})
            .subscribe(users => this.users = users,
                error =>this.errorMessage =<any> error);

        return this.users;

    }

However this line .filter(users => { is giving me an error saying:

Argument of type '(users: User[]) => void' is not assignable to 
parameter of type '(value: User[], index: number) => boolean'. Type 
'void' is not assignable to type 'boolean

I later try to use this to initialize the variable so I can populate it on a different form.

case "lastName":
                this.users = this.getUserByLastName(this.lastName);

If that is confusing, I have two pages. One is hidden until a row is click in the default page. A form is in the other one (the hidden one) which populates data for the user (row) selected in a form to edit.

eko · Accepted Answer · 2017-03-10 19:46:53Z

3

I assume you can have different term upon you want to filter. If not you can already pass the lastname to the service to filter, but if you want to filter in the component do the following. If you need to return the filtered data, as it seems, return it, and where you need it, subscribe. So:

getUserByLastName(lastName){
   return this._searchService.getUsers()
      .map(data => {
         return data.filter((x: any) => x.lastName == lastName);
      })
}

and where you need it, subscribe:

this.getUserByLastName(this.lastName)
  .subscribe(data => {
     this.users = data;
  });

edited Mar 10, 2017 at 19:46

eko

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answered Mar 10, 2017 at 19:31

AVJT82

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Comments

Aravind · Accepted Answer · 2017-03-10 19:42:56Z

1

This can be easily achieved using lodash as below

users =<User[]> _.pullAllWith(users,{lastName : 'yourparameter'}, _.isEqual);

answered Mar 10, 2017 at 19:42

Aravind

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