T9 Keyboard Emulator Online

What is T9? T9 (Text on 9 keys) is a predictive text technology from the late 1990s/early 2000s that allowed users to type on mobile phones with 9 number keys (2-9). Each key maps to multiple letters, and T9 predicts the intended word based on key sequences. Key Mapping Key 2: ABC Key 3: DEF Key 4: GHI Key 5: JKL Key 6: MNO Key 7: PQRS Key 8: TUV Key 9: WXYZ Key 0: Space Key 1: Punctuation (varies by implementation) How to Build a T9 Emulator Step 1: Create the Letter-to-Key Mapping # Python example letter_to_key = 'a': '2', 'b': '2', 'c': '2', 'd': '3', 'e': '3', 'f': '3', 'g': '4', 'h': '4', 'i': '4', 'j': '5', 'k': '5', 'l': '5', 'm': '6', 'n': '6', 'o': '6', 'p': '7', 'q': '7', 'r': '7', 's': '7', 't': '8', 'u': '8', 'v': '8', 'w': '9', 'x': '9', 'y': '9', 'z': '9', ' ': '0'

pressKey(key) if (key === '0') // Space - accept current word this.acceptWord(); return; this.currentSequence += key; this.predictions = this.dictionary[this.currentSequence] t9 keyboard emulator

// Usage const t9 = new T9Emulator(); t9.loadDictionary(['hello', 'good', 'home', 'test', 'world']); console.log(t9.pressKey('4')); // ['good', 'home'] for '4'? Actually '4' = ghi console.log(t9.pressKey('6')); // ['home'] for '46'? Wait, '46' = 'hm'? Let's fix... Here's a starter dictionary with common words: What is T9

Store common words mapped to their T9 sequences: Key Mapping Key 2: ABC Key 3: DEF

acceptWord()

loadDictionary(words) words.forEach(word => const seq = this.wordToSequence(word); if (!this.dictionary[seq]) this.dictionary[seq] = []; this.dictionary[seq].push(word); );