This txtboxempty validating
If you run it nothing happens when you click the buttons or enter text, but if you maximize or pull in the dialog, the controls behave exactly as you want them to in a proper user interface, staying put and resizing to fill the whole of the dialog. You insert the information the user has entered without bothering to check if it is correct.This means that you must do the checking elsewhere.This is because you need another check to see if anything was entered at all.This is a simple thing as you've already written the method to perform this check, and you simply subscribe to the button while in a text box with invalid data without the background color changing to red.
The primary function of a text box is for users to enter text, but any characters can be entered, and it is quite possible to force users to enter numeric values only. NET Framework comes with two basic controls to take text input from users: provides the base functionality for text manipulation in a text box, such as selecting text, cutting to and pasting from the Clipboard, and a wide range of events.
The example you just completed is quite long compared to the others you will see in this chapter — this is because you build on this example rather than starting from scratch with each example.
This is the forum to discuss the Wrox book Beginning Visual C#, Revised Edition of Beginning C# for .
The Java programming language distinguishes between null and empty strings.
An empty string is a string instance of zero length, whereas a null string has no value at all.