我如何使用switch语句而不是太多其他语句

Question

Hello please help me out in writing switch statement for the below else if statement

if(ClientAddressTextBox.Text == "")
            {

                MessageBox.Show("Please Enter Client Address");
                this.ActiveControl = ClientAddressTextBox;
            }

            else if (InnerpathTextBox.Text == "")
            {
                MessageBox.Show("Please Enter Internal Path");
                this.ActiveControl = InnerpathTextBox;
            }

            else if (InspectorIDTextBox.Text == "")
            {
                MessageBox.Show("Please Enter Inspector ID");
                this.ActiveControl = InspectorIDTextBox;
            }

            else if (SerialNumberTextBox.Text == "")
            {

                MessageBox.Show("Please Enter Serial Number");
                this.ActiveControl = SerialNumberTextBox;
            }

Answer 1

You could do something like this:

var controls = new []
{
    new {Ctrl = InnerpathTextBox,     Error = "Please Enter Client Address"},
    new {Ctrl = ClientAddressTextBox, Error = "Please Enter Internal Path"},
    new {Ctrl = InspectorIDTextBox,   Error = "Please Enter Inspector ID"},
    new {Ctrl = SerialNumberTextBox,  Error = "Please Enter Serial Number"}
};

var firstToFailValidation = controls.FirstOrDefault(item => item.Ctrl.Text == "");

if (firstToFailValidation != null)
{
    MessageBox.Show(firstToFailValidation.Error);
    this.ActiveControl = firstToFailValidation.Ctrl;
}

You might want to check for nulls though. This code assumes that none of the controls or the .Text properties are null.

Answer 2

I'd approach this as follows:

var validationMessages = new[]{new{Control = InnerpathTextBox, 
                                   Message = "Please Enter Internal Path"},
                               new{Control = InspectorIDTextBox, 
                                   Message = "Please Enter Inspector Id"},
                               //etc
};
foreach(var vm in validationMessages)
{
    if(string.IsNullOrWhiteSpace(vm.Control.Text))
    {
        MessageBox.Show(vm.Message);
        this.ActiveControl = vm.Control;
        break;
    }
}

Answer 3

You can use Something like this:

private bool IfTextBoxEmpty(string text, string message, Control control)
    {
        if (text == "")
        {
            MessageBox.Show(message);
            this.ActiveControl = control;
            return true;
        }
        return false;
    }

And the Usage:

if (!IfTextBoxEmpty(ClientAddressTextBox.Text, "Please Enter Client Address", ClientAddressTextBox)
{
            //if not - Do Something
}

Answer 4

This is a pseudo code for a switch statement.

string statement;
switch(statement)
{
    case (ClientAddressTextBox.Text == ""):
    MessageBox.Show("Please Enter Client Address");
    this.ActiveControl = ClientAddressTextBox; 
    break;

    case (InnerpathTextBox.Text == ""):
    ...
}

and so on.