how to use parent module component in child module component in angular2

Question

I have header that should be used in both child and parent module.that was imported and used in parent module but when try to import and using in child component it showing erro

Answer 1

You should create a shared module with the components you want to use, export these components, and import the shared module in your other modules (parent and child for your case).

Shared module:

import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
import { SharedComponent1 } from "./SharedComponent1";
import { SharedComponent2 } from "./SharedComponent2";

@NgModule({
imports: [
    CommonModule
],
declarations: [
    SharedComponent1,
    SharedComponent2
],
exports: [
    SharedComponent1,
    SharedComponent2
]
})
export class SharedModule {}

Using Shared module:

import { NgModule }       from '@angular/core';
import { CommonModule }   from '@angular/common';
...
import { SharedModule } from './SharedModule';

@NgModule({
imports: [
    CommonModule,
    ...
    SharedModule
],
declarations: [
    ...
],
providers: [
    ...
]
})
export class AppModule{}

Answer 2

It would have been great , if you can share the code and the specified the error you are getting.

As per my understanding , you basically want to pass some data from parent component to its child component .

For this , you need to use @Input to pass parent params to child.

Component Interaction between parent and child

Let me know , if it helps or not