title: Binding selected value from mat-select form to be passed to submit button function
body: <p>Updated in reference to German's answer</p>
  
  <p>I am trying to pass the instrumentName field from the instrument value selected by the user to the function in the submit button. The instrumentName value shows up properly, but it never seems to be saved upon submitting. All of the other input values save fine. How can I fix this?</p>
  
  <p>HTML:</p>
  
  <pre><code>      &lt;form [formGroup]="createForm" class="create-form"&gt;
  
          &lt;/mat-form-field --&gt;
          &lt;mat-form-field class="field-full-width"&gt;
              &lt;mat-label&gt;Instrument&lt;/mat-label&gt;
              &lt;mat-select matInput formControlName="createForm.get('Machine_ID')" #Machine_ID&gt;
                  &lt;mat-option *ngFor="let instrument of instruments" [value]="instrument.instrumentName"&gt;
                      {{instrument.instrumentName}}
                    &lt;/mat-option&gt;
              &lt;/mat-select&gt;
          &lt;/mat-form-field&gt;
          &lt;button mat-raised-button color="accent" routerLink="/list"&gt;Back&lt;/button&gt;&amp;nbsp;
          &lt;button  (click)="addSample()"
            [disabled]="createForm.invalid"  color="primary"&gt;Save&lt;/button&gt;
        &lt;/form&gt;
  </code></pre>
  
  <p>TS code: </p>
  
  <pre><code>import { Component, OnInit } from '@angular/core';
  import { FormGroup, FormBuilder, Validators } from '@angular/forms';
  import { Router } from '@angular/router';
  import { FileService } from '../../file.service';
  import { Instrument } from '../../instrument.model';
  @Component({
    selector: 'app-add-new-sample',
    templateUrl: './add-new-sample.component.html',
    styleUrls: ['./add-new-sample.component.css']
  })
  export class AddNewSampleComponent implements OnInit {
    createForm: FormGroup;
    instruments: Instrument[];
    constructor(private fileService: FileService, private fb: FormBuilder, private router: Router) {
      this.createForm = this.fb.group({
  
        Machine_ID: '',
  
      });
  
      }
      addSample() {
        const machineIdValue = this.createForm.get('Machine_ID').value;
        this.fileService.addSample(machineIdValue).subscribe(() =&gt; {
          this.router.navigate(['/instruments']);
        });
      }
      fetchInstruments(){
        this.fileService.getInstruments()
        .subscribe((data: Instrument[])=&gt;
        {
          this.instruments = data;
  
        })
      }
    ngOnInit() {
      this.fetchInstruments();
    }
  
  }
  </code></pre>