- Processing
- p5.js
- Processing.py
- Processing for Android
- Processing for Pi

- Processing Foundation

This reference is for Processing 3.0+. If you have a previous version, use the reference included with your software in the Help menu. If you see any errors or have suggestions, please let us know. If you prefer a more technical reference, visit the Processing Core Javadoc and Libraries Javadoc.

Name | ### key
Examples |
    // Click on the window to give it focus,
    // and press the 'B' key.

    void draw() {
      if (keyPressed) {
        if (key == 'b' || key == 'B') {
          fill(0);
        }
      } else {
        fill(255);
      }
      rect(25, 25, 50, 50);
    }
Description | The system variable key always contains the value of the most recent key on the keyboard that was used (either pressed or released). For non-ASCII keys, use the keyCode variable. The keys included in the ASCII specification (BACKSPACE, TAB, ENTER, RETURN, ESC, and DELETE) do not require checking to see if the key is coded, and you should simply use the key variable instead of keyCode If you're making cross-platform projects, note that the ENTER key is commonly used on PCs and Unix and the RETURN key is used instead on Macintosh. Check for both ENTER and RETURN to make sure your program will work for all platforms. There are issues with how keyCode behaves across different renderers and operating systems. Watch out for unexpected behavior as you switch renderers and operating systems.
Related | keyCode keyPressed keyPressed() keyReleased()

Updated on January 1, 2021 03:38:09am EST
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