How to call a components public method from its parent?

Question

So I want to call the OpenModal() method in the child component (TimeEntryForm). I would think I need to access the instance of TimeEntryForm component, but I don't know how to create a named instance of TimeEntryForm.

Any help would be appreciated.

Parent Component

<button type="button" onclick="@TimeEntryForm.OpenModal()" class="btn btn-info btn-lg">
    <span class="glyphicon glyphicon-plus"></span> Add
</>

<TimeEntryForm></TimeEntryForm>

TimeEntry Child Component

@using Chopper.Shared
@using DatabaseModel.Models
@page "/timeentryform"
@inject HttpClient HTTP
@inherits TimeEntryFormModel

@if (IsOpened)
{
    <div class="modal" role="dialog" tabindex="-1" style="display: block;">
        <div class="modal-dialog modal-dialog-centered" role="document">
            <div class="modal-content">
                <div class="modal-header">
                    <h5 class="modal-title">Add a Time Entry</h5>
                </div>
                <div class="modal-body">

                    <form>
                        <div class="form-group">
                            <label for="Job" class="col-form-label">Job:</label>
                            <input type="text" class="form-control" />
                        </div>
                        <div class="form-group">
                            <label for="Employee" class="col-form-label">Employee:</label>
                            <input class="form-control" type="text" />
                        </div>
                        <div class="form-group">
                            <label for="Hours" class="col-form-label">Hours:</label>
                            <input class="form-control" type="text" />
                        </div>
                    </form>

                </div>
                <div class="modal-footer">
                    <button type="button" class="btn btn-primary" onclickAsync="@OnAddTimeEntry()">Add Entry</button>
                    <button type="button" class="btn btn-primary" onclick="@CloseModal">Close</button>
                </div>
            </div>
        </div>
    </div>
    <div class="modal-backdrop show"></div>
}

Time Entry Child Component code behind view model

using Chopper.Client.TimeEntries.Services;
using DatabaseModel.Models;
using Microsoft.AspNetCore.Blazor.Components;
using System.Threading.Tasks;

namespace Chopper.Client.TimeEntries
{
    public class TimeEntryFormModel : BlazorComponent
    {
        protected TimeEntry TimeEntry = new TimeEntry();

        [Inject]
        private TimeEntriesServices _client { get; set; }

        protected bool IsOpened { get; set; }

        public void OpenModal()
        {
            IsOpened = true;
            StateHasChanged();
        }

        //[Parameter]
        protected void CloseModal()
        {
            IsOpened = false;
            StateHasChanged();
        }

        protected async Task OnAddTimeEntry()
        {

            if (TimeEntry.Job != null && TimeEntry.Category != null && TimeEntry.TimeSpentHours > 0 && TimeEntry.Employee != null)
            {
                await _client.CreateTimeEntry(TimeEntry);
                await OnInitAsync();
                StateHasChanged();
                //return true;
            }
            //return false;
        }

    }
}

Answer 1

So I needed to add a protected member in the parent component model of protected TimeEntryForm timeEntryForm = new TimeEntryForm();

and then do a reference to it in the view as <TimeEntryForm ref="timeEntryForm"></TimeEntryForm>

Parent Component

<button type="button" onclick="@timeEntryForm.OpenModal()" class="btn btn-info btn-lg">
    <span class="glyphicon glyphicon-plus"></span> Add
</>

<TimeEntryForm ref="timeEntryForm"></TimeEntryForm>

Parent Component code behind model/viewmodel

public class TimeEntriesGridModel : BlazorComponent
{
    [Inject]
    private TimeEntriesServices _client { get; set; }

    protected TimeEntryForm timeEntryForm; // = new TimeEntryForm(); //Per Kirk Woll's suggestion

    protected List<TimeEntry> Model { get; set; }

    protected override async Task OnInitAsync()
    {
        Model = await _client.GetAllTimeEntries();
    }


}

TimeEntry Child Component

@using Chopper.Shared
@using DatabaseModel.Models
@page "/timeentryform"
@inject HttpClient HTTP
@inherits TimeEntryFormModel

@if (IsOpened)
{
    <div class="modal" role="dialog" tabindex="-1" style="display: block;">
        <div class="modal-dialog modal-dialog-centered" role="document">
            <div class="modal-content">
                <div class="modal-header">
                    <h5 class="modal-title">Add a Time Entry</h5>
                </div>
                <div class="modal-body">

                    <form>
                        <div class="form-group">
                            <label for="Job" class="col-form-label">Job:</label>
                            <input type="text" class="form-control" />
                        </div>
                        <div class="form-group">
                            <label for="Employee" class="col-form-label">Employee:</label>
                            <input class="form-control" type="text" />
                        </div>
                        <div class="form-group">
                            <label for="Hours" class="col-form-label">Hours:</label>
                            <input class="form-control" type="text" />
                        </div>
                    </form>

                </div>
                <div class="modal-footer">
                    <button type="button" class="btn btn-primary" onclickAsync="@OnAddTimeEntry()">Add Entry</button>
                    <button type="button" class="btn btn-primary" onclick="@CloseModal">Close</button>
                </div>
            </div>
        </div>
    </div>
    <div class="modal-backdrop show"></div>
}

Time Entry Child Component code behind view model

using Chopper.Client.TimeEntries.Services;
using DatabaseModel.Models;
using Microsoft.AspNetCore.Blazor.Components;
using System.Threading.Tasks;

namespace Chopper.Client.TimeEntries
{
    public class TimeEntryFormModel : BlazorComponent
    {
        protected TimeEntry TimeEntry = new TimeEntry();

        [Inject]
        private TimeEntriesServices _client { get; set; }

        protected bool IsOpened { get; set; }

        public void OpenModal()
        {
            IsOpened = true;
            StateHasChanged();
        }

        //[Parameter]
        protected void CloseModal()
        {
            IsOpened = false;
            StateHasChanged();
        }

        protected async Task OnAddTimeEntry()
        {

            if (TimeEntry.Job != null && TimeEntry.Category != null && TimeEntry.TimeSpentHours > 0 && TimeEntry.Employee != null)
            {
                await _client.CreateTimeEntry(TimeEntry);
                await OnInitAsync();
                StateHasChanged();
                //return true;
            }
            //return false;
        }

    }
}

EIA:

Removed code behind initialization for timeEntryForm per Kirk Woll's suggestion.