在Angular中如何监听某个值的变化

import { Component } from '@angular/core';
@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.CSS']
})
export class AppComponent {

  _inputVal;

  set inputVal(val) {
    this._inputVal = val;
    this.inputChange();
  };

  get inputVal() {
    return this._inputVal;
  }

  inputChange(val) {
    console.log(val);
  }
}

import {
 Validators,
 FormGroup,
 FormBuilder
} from '@angular/forms';

    validateForm: FormGroup;
    constructor(private fb: FormBuilder,private ref: ChangeDetectorRef,private private) {}

  data = {
      name: [null, [Validators.required]], //Validators.required 表示验证（必填）
  };
  nGonInit(): void {
    this.validateForm = this.fb.group(this.data);
    // 监听整个表单的变化
    this.validateForm.valueChanges.subscribe(data => console.log('form', data));
    // 单个control 变化
    this.validateForm.get('name').valueChanges.subscribe(data => console.log('solo', data));
  }