How to Know if a JTextField Is Empty

The JTextField Java control displays a text box in which a user sends you feedback on the desktop form. The JTextField control is a standard input field data type used in most desktop applications. To determine if the user has entered text, you use the "getText" function and evaluate if the input is a zero-length string.

Instructions

1. Open the Java development software you use to create your apps. Open the project you want to edit and the form source code that contains your JTextField control.

2. Get the text in the control using the "getText" function. The following code gets the text from the control named "mytb" and assigns the value to the variable named "input":

   string input = mytb.getText();

3. Evaluate if the text is empty and display a message to the user. You can use this function to ask the user to enter data and verify that input is typed in the text box. The following code determines if the text box is empty:

   if (input == "") {
   system.out.println("Please enter a value");
   }

References

• Lee Point: Java: JTextField