Doubt about implementing a Dependency Injection in C # using Ninject

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Doubt about implementing a Dependency Injection in C # using Ninject

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#1 by (1 votes)

1

I have a C # project with Windows Forms. I have a question about how to do an implementation between two layers of my application: Application and WindowsForms .

I need to load a DataGridView with a list of "PessoaTipo" .

I created an instance of my Application class PessoaTipoAppService in WindowsForms and called the function _PessoaTipoApp.GetAll() , but when I load it through the constructor , it fails because of the implementation of Dependency Injection with Ninject.

public partial class Form1 : Form
    {
        private readonly IPessoaTipoAppService _PessoaTipoApp;

        public Form1(IPessoaTipoAppService PessoaTipoApp)
        {
            InitializeComponent();

            _PessoaTipoApp = PessoaTipoApp;

            dataGridView1.DataSource = _PessoaTipoApp.GetAll();
        }
    }

Could someone give me strength? I left the project available for download. Then we can post the solution here in this topic ...

c# entity-framework ninject

asked by anonymous 14.02.2017 / 23:31

1 answer

Passing correct parameters on Form submit I wanted to improve the performance of my program

score 1 · Answer 1

Minimum Example:

Install the package by Nuget or Package Manager Console

Install-Package Ninject

Create a class that is responsible for resolving dependencies:

FormModule

using Ninject.Modules;
public class FormModule : NinjectModule
{
    public override void Load()
    {
        Bind<IMount>().To<Mount>();
    }

    public static FormModule Create()
    {
        return new FormModule();
    }
}

In the Load method call Bind to class configuration and place all classes that will be used in your project and which are dependencies of other forms.

Create a class that will be responsible for instantiating the Form and consequently the their dependencies :

FormResolve

using Ninject;
using Ninject.Modules;
public class FormResolve
{
    private static IKernel _ninjectKernel;

    public static void Wire(INinjectModule module)
    {
        _ninjectKernel = new StandardKernel(module);
    }

    public static T Resolve<T>()
    {
        return _ninjectKernel.Get<T>();
    }
}

In the file Program.cs set as follows:

using System;
using System.Windows.Forms;

namespace WindowsFormsApplication3
{
    static class Program
    {
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);

            FormResolve.Wire(FormModule.Create());
            Application.Run(FormResolve.Resolve<Form1>());
        }    
    }
}

With these two classes and the configuration made in Program.cs is ready to resolve dependencies.

Example: Form1

using Ninject;
using System.Windows.Forms;  
namespace WindowsFormsApplication3
{
    public partial class Form1 : Form
    {

        private IMount Mount { get; set; }

        [Inject()]
        public Form1(IMount mount)
        {
            InitializeComponent();
            Mount = mount;
        }

        private void Form1_Load(object sender, System.EventArgs e)
        {
            label1.Text = Mount?.GetDateTime().ToLongDateString();

        }

        private void button1_Click(object sender, System.EventArgs e)
        {
            Form2 frm = FormResolve.Resolve<Form2>();
            frm.ShowDialog();
        }
    }
}

To call form2 or any form follow the example of the button below where form1 calls form2 :

private void button1_Click(object sender, System.EventArgs e)
{
    Form2 frm = FormResolve.Resolve<Form2>();
    frm.ShowDialog();
}

References: