Calling method from another class - Winforms C#-CodePudding

I am trying something like below and I am getting red lines under any formDesign commands such as messageBox, dataGridView etc.

I want to put the body of the methods in a seperate .cs page for neatness and call them from mainForm.cs

Is this the wrong way to call methods

mainForm.cs

namespace App{
      public partial class mainForm : Form{
             private void saveCSVbutton_Click(object sender, EventArgs e){
                className.method();
             }
      }
}

class.cs

namespace App{
      class className{
              private void method(){MessageBox.Show("No Record To Export", "Info");}
      }
}

CodePudding user response：

If you just want put some code in a function, you should declare the function like

public static class MyClass{
      public static void MyMethod(){...}
}

If you only need the method from within the same project you can replace public with internal.

A static method is appropriate if the method only depends on the given parameters, if it needs to maintain a state you need to remove the static, create an object of the class in your form, and use that object to call the method.

CodePudding user response：

If you want to separate different layers of an app, I suggest you use a design pattern like MVVM. This way you would have classes that does the functionality of the app and other classes work with database and so on.