Displaying<List> reports in a message box

Question

Within my WinForm i have a method that checks the validation of various user controls and adds them to an errorList. When the user clicks the save button I want it to check the validation method and show the errors if any in a message box. The Validate method is in another form and class so i think that might be my problem.

 private void Save_Click(object sender, EventArgs e)
    {
        var errorList = string.Join(Environment.NewLine, Validate.ToArray());
        MessageBox.Show(errorSet);

    }

Thank you for any help.

Answer 1

The error 'Form1.Validate(System.Collections.Generic.List<string>)' is a 'method', which is not valid in the given context means that you're using the method wrong.

var errorList = string.Join(Environment.NewLine, Validate.ToArray());

makes no sense. You're missing the parentheses:

var errorList = string.Join(Environment.NewLine, Validate().ToArray());

That's only one problem. The method has a parameter of type List<string> , but you don't pass an argument to the function.

Also, you said in a comment that the return value is of type bool , but it seems you expect it to return a collection of strings.

Answer 2

You have this issue because you are calling the validate method that is on another form without mentioning the instance of that form.

Lets say you have another class Class1.

 //create instance of your class/form that has this method
 OperationControl oc  = new OperationControl ();

 private void Save_Click(object sender, EventArgs e)
    {
        //call the method with form instance created above
        var errorList = string.Join(Environment.NewLine, oc.Validate().ToArray());
        MessageBox.Show(errorSet);

    }

Answer 3

some time this error means you may have the same method with the same name in your program scope. Check if no other function named MessageBox exist in your program