Scanner & Keyboard Input Handler

中文文档 (Chinese)

A robust, IE6-compatible JavaScript library for handling Barcode Scanner and Keyboard inputs in web applications.

Features

• Dual Mode Detection: Automatically distinguishes between manual keyboard input and high-speed scanner input.
• IE6 Compatible: Validated support for legacy browsers (IE6+), including json2.js integration for JSON parsing.
• Event Separation: Uses keypress for accurate character capture (fixing legacy keydown issues with symbols like { or ") and keydown for control keys.
• Buffering & validation: Built-in input buffering, length limits, and custom validation.
• Throttle Control: Prevents duplicate submissions.
• Rich Callbacks: Hooks for Scan Start, Input, Complete, Error, etc.

Installation

Simply include the scripts in your HTML file.

<!-- For IE6/7 support -->
<script src="json2.js"></script>
<!-- Main Library -->
<script src="main.js"></script>

Usage

1. Initialize

var scanner = new ScannerKeyboardInput({
    // Configuration
    maxCodeLength: 8,
    scanTimeout: 200, // ms
    
    // Callbacks
    onScanComplete: function(code) {
        console.log("Scanned Code:", code);
        // Do ajax post...
    },
    onKeyboardComplete: function(code) {
        console.log("Keyboard Input:", code);
    },
    onError: function(msg) {
        alert("Error: " + msg);
    }
});

// Automatically bind events to document
scanner.init();

// Or bind to a specific element
// scanner.init(document.getElementById('app'));

2. Configuration Options

| Option | Type | Default | Description |

Prefix	Type	Default	Description
maxCodeLength	Number	8	Max length for keyboard input buffering.
scanTimeout	Number	2000	Timeout to reset scanner buffer (ms).
throttleInterval	Number	3000	Time to wait before allowing duplicate submission (ms).
scanStartKeyCode	Number	219	KeyCode for scanner start char (default: {).
scanEndKeyCode	Number	221	KeyCode for scanner end char (default: }).
shouldSubmit	Function	null	Custom validator. Return false to cancel submission.

3. Callbacks

• onScanStart(): Triggered when scanner start sequence is detected.
• onScanInput(val): Triggered on every char during scan.
• onScanComplete(code): Triggered when scan is finished and parsed.
• onKeyboardInput(char, loc, fullCode): Triggered on manual key press.
• onKeyboardComplete(code): Triggered when manual input reaches maxCodeLength.
• onError(msg): Triggered on JSON parse error or other failures.

Browser Support

• Chrome, Firefox, Safari, Edge (Modern)
• Internet Explorer 6, 7, 8, 9+

License

MIT