单击保存按钮时如何检测所有文本框是否为空

Question

I have a question about there are 30 textboxes on a windows form. I am trying to test the application.

All textboxes have validation event for you enter, keypresses and leave events.

But the problem when open the page and directly pressed the button it saves textboxess without warning.

How to handele all textboxes empty situation without checking each of them with conditions like

      if(String.isNotNullorEpty(textbox1.Text)&&...)

thanks.

Answer 1

You can simply loop thru all textbox controls and check if one of them has text.If only 1 out of 30 has text then your condition is false.

    bool allEmpty = true;
    foreach (Control c in Controls)
    {   
        if(c is TextBox tb && !String.IsNullOrEmpty(tb.Text))
        {
            allEmpty = false;
            break;
        }   
    }   

Answer 2

Using linq:

bool allEmpty = parentControl.Controls.OfType<TextBox>().All(tb => tb.Text == "");

Just set your 'parentControl'.

Answer 3

There is no need to check all textboxes, or any other loop.

Keep your save changes button disabled. You have events for every textbox already, just add to this events to enable the save changes button when text is changing. This way it is not possible anymore to save changes immediate when the form has opened

Another advantage of this method is that when the user closes the form you can check if there are any unsaved changes, and ask if he wants to save them before closing.