每次我按下按钮时，我希望它指示 C# 中我的文本框或文本框何时为空

Question

Evertime I press a button I want it to indicate when my textbox or textboxes are empty. Because there's 3 and I need this error to come up even when one out of all is empty. If all textboxes are filled up I want my progress bar to start loading too. I'd really appreciate your help!

Answer 1

create keydown event for all textboxes same, and call the function

public void checkstatus()
{
if(textbox1.Text.Trim()=="" || textbox2.Text.Trim()=="" || textbox3.Text.Trim()=="")
{
 MessageBox.Show("Some Textboxes are empty");
}
else
{
 progessbar.Start();
}

}