How to recall a method of class in An event of form

Question

This is my class:

public class CowTypeDefaults
{
  public static void LactatingCow()
    {
        Form1 frm = new Form1();
        {
            frm.CowAgetxtBox.Enabled = true;
            frm.CowWeighttxtBox.Enabled = true;
            frm.DaysPregtxtBox.Enabled = true;
            frm.BCStxtBox.Enabled = true;
            frm.DaysInMilktxtBox.Enabled = true;
            frm.LactationNumbertxtBox.Enabled = true;
            frm.FirstCalftxtBox.Enabled = true;
            frm.CalfInttxtBox.Enabled = true;
            frm.ADGpanel.Visible = false;
            frm.CalfVarGroupBox.Enabled = false;
        }
    }
}

And I want to recall lactatingCow() in an event of my form and this is how i recall it:

private void CowTypeSelect_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (CowTypeSelect.SelectedIndex == 0)
            {
                CowTypeDefaults.LactatingCow();
            }
        }

It shows no error and program runs but the code doesn't work and my text boxes are still disabled.

I don't know how fix it, thanks a lot for answering.

Answer 1

Because you are re-initiating Form1 frm = new Form1(); in the static method, so that in each call frm will be different. Since this file is a separate class better option is to pass the object. So the method signature will be like:

 public static void LactatingCow(Form1 frm)
     {
        frm.CowAgetxtBox.Enabled = true;
        frm.CowWeighttxtBox.Enabled = true;
        frm.DaysPregtxtBox.Enabled = true;
        frm.BCStxtBox.Enabled = true;
        frm.DaysInMilktxtBox.Enabled = true;
        frm.LactationNumbertxtBox.Enabled = true;
        frm.FirstCalftxtBox.Enabled = true;
        frm.CalfInttxtBox.Enabled = true;
        frm.ADGpanel.Visible = false;
        frm.CalfVarGroupBox.Enabled = false;
    }

And the button click will be :

private void CowTypeSelect_SelectedIndexChanged(object sender, EventArgs e)
    {
        if (CowTypeSelect.SelectedIndex == 0)
        {
            CowTypeDefaults.LactatingCow(this);
        }
    }

Answer 2

Well you're creating a new instance of Form1 everytime. Pass your form's instance as reference to you method:

public static void LactatingCow(Form1 form)
{
    form.CowAgetxtBox.Enabled = true;
    form.CowWeighttxtBox.Enabled = true;
    form.DaysPregtxtBox.Enabled = true;
    form.BCStxtBox.Enabled = true;
    form.DaysInMilktxtBox.Enabled = true;
    form.LactationNumbertxtBox.Enabled = true;
    form.FirstCalftxtBox.Enabled = true;
    form.CalfInttxtBox.Enabled = true;
    form.ADGpanel.Visible = false;
    form.CalfVarGroupBox.Enabled = false;
}

and call it using this as well:

private void CowTypeSelect_SelectedIndexChanged(object sender, EventArgs e)
{
    if (CowTypeSelect.SelectedIndex == 0)
        CowTypeDefaults.LactatingCow(this);
}

Answer 3

I think define a delegate can slove you question. Define a delegate base on you target method, and declare a public varable of that delegate in class Form, named it Degegate temporary. When Form frm = new Form(); use frm.Delegate receive target method, then execcute that delegate varable in you class Form 's event which you need. I'm answer you question on mobelphone, so I can't change code style, sorry