_setKeyComposition(config){ var altKey = config.alt; var ctrlKey = config.ctrl; var shiftKey = config.shift; var threeKey = altKey && ctrlKey && shiftKey; var ctrlAlt = altKey && ctrlKey; var altShift = altKey && shiftKey; var ctrlShift = shiftKey && ctrlKey; var code = config.code + ''; if(threeKey){ this.keyTypeSet.threeKey[code] = config.type; } else if(ctrlAlt) { this.keyTypeSet.ctrlAlt[code] = config.type; } else if(ctrlShift) { this.keyTypeSet.ctrlShift[code] = config.type; } else if(altShift) { this.keyTypeSet.altShift[code] = config.type; } else if(altKey) { this.keyTypeSet.altKey[code] = config.type; } else if(ctrlKey) { this.keyTypeSet.ctrlKey[code] = config.type; } else if(shiftKey) { this.keyTypeSet.shiftKey[code] = config.type; } else { this.keyTypeSet.singleKey[code] = config.type; } return null; };
这样，一个键盘事件监听控件就大功告成了，下面是完整实现代码：
/** * @constructor 键盘事件监听器 * */ function KeyboardListener(param){ this._init(param); } !function(){ /** * @private {String} param.ele 事件对象选择器 * */ KeyboardListener.prototype._init = function _init(param){ this.$ele = $(param.ele); this._initEvents(); this._initEventType(); return null; }; /** * @private _emptyEventHandler 空白事件响应 * */ KeyboardListener.prototype._emptyEventHandler = function _emptyEventHandler(){ return null; }; /** * @private _initEventType 初始化所有初始自定义事件类型 * */ KeyboardListener.prototype._initEventType = function _initEventType(){ var allType = ['up', 'down', 'left', 'right', 'undo', 'redo', 'zoomIn', 'zoomOut', 'delete']; var intLen = allType.length; this.allEventType = allType; this.callback = {}; this.eventDiscibeSet = {}; for(var intCnt = 0; intCnt < intLen; intCnt++){ this.callback['on' + allType[intCnt]] = KeyboardListener.prototype._emptyEventHandler; } return null; }; /** * @private _initEvents 绑定 DOM 事件 * */ KeyboardListener.prototype._initEvents = function _initEvents(){ var $ele = this.$ele; $ele.attr('tabindex', 1); $ele.on('mouseenter', function(){ $ele.focus(); }); $ele.on('keydown', this._keyDownHandler.bind(this)); this.keyTypeSet = { altKey: {}, ctrlAlt: {}, ctrlKey: {}, threeKey: {}, altShift: {}, shiftKey: {}, ctrlShift: {}, singleKey: {} }; // 支持一些内建的键盘事件类型 this.extendEventType([ { type: 'redo', ctrl: true, shift: true, code: 90 }, { type: 'undo', ctrl: true, code: 90 }, { type: 'copy', ctrl: true, code: 67 }, { type: 'paste', ctrl: true, code: 86 }, { type: 'delete', code: 46 }, { type: 'right', code: 39 }, { type: 'down', code: 40 }, { type: 'left', code: 37 }, { type: 'up', code: 38 } ]); return null; }; /** * @private _keyDownHandler 自定义键盘事件分发 * */ KeyboardListener.prototype._keyDownHandler = function _keyDownHandler(e){ var strCommand = this._keyCodeProcess(e); var objEvent = { type: '', originEvent: e.originEvent }; strCommand && this.callback['on' + strCommand](objEvent); return null; }; /** * @private _keyCodeProcess 处理按键码 * */ KeyboardListener.prototype._keyCodeProcess = function _keyCodeProcess(e){ var code = e.keyCode + ''; var altKey = e.altKey; var ctrlKey = e.ctrlKey; var shiftKey = e.shiftKey; var threeKey = altKey && ctrlKey && shiftKey; var ctrlAlt = altKey && ctrlKey; var altShift = altKey && shiftKey; var ctrlShift = shiftKey && ctrlKey; var keyTypeSet = this.keyTypeSet; var resStr = ''; if(threeKey){ resStr = keyTypeSet.threeKey[code]; } else if(ctrlAlt) { resStr = keyTypeSet.ctrlAlt[code]; } else if(ctrlShift) { resStr = keyTypeSet.ctrlShift[code]; } else if(altShift) { resStr = keyTypeSet.altShift[code]; } else if(altKey) { resStr = keyTypeSet.altKey[code]; } else if(ctrlKey) { resStr = keyTypeSet.ctrlKey[code]; } else if(shiftKey) { resStr = keyTypeSet.shiftKey[code]; } else { resStr = keyTypeSet.singleKey[code]; } return resStr }; /** * @private _setKeyComposition 自定义键盘事件 * @param {Object} config 键盘事件配置方案 * @param {String} config.type 自定义事件类型 * @param {keyCode} config.code 按键的码值 * @param {Boolean} [config.ctrl] 是否与 Ctrl 形成组合键 * @param {Boolean} [config.alt] 是否与 Alt 形成组合键 * @param {Boolean} [config.shift] 是否与 Shift 形成组合键 * */ KeyboardListener.prototype._setKeyComposition = function _setKeyComposition(config){ var altKey = config.alt; var ctrlKey = config.ctrl; var shiftKey = config.shift; var threeKey = altKey && ctrlKey && shiftKey; var ctrlAlt = altKey && ctrlKey; var altShift = altKey && shiftKey; var ctrlShift = shiftKey && ctrlKey; var code = config.code + ''; if(threeKey){ this.keyTypeSet.threeKey[code] = config.type; } else if(ctrlAlt) { this.keyTypeSet.ctrlAlt[code] = config.type; } else if(ctrlShift) { this.keyTypeSet.ctrlShift[code] = config.type; } else if(altShift) { this.keyTypeSet.altShift[code] = config.type; } else if(altKey) { this.keyTypeSet.altKey[code] = config.type; } else if(ctrlKey) { this.keyTypeSet.ctrlKey[code] = config.type; } else if(shiftKey) { this.keyTypeSet.shiftKey[code] = config.type; } else { this.keyTypeSet.singleKey[code] = config.type; } return null; }; /** * @method extendEventType 扩展键盘事件类型 * @param {Object|Array<object>} config 键盘事件配置方案 * @param {String} config.type 自定义事件类型 * @param {keyCode} config.code 按键的码值 * @param {Boolean} [config.ctrl] 是否与 Ctrl 形成组合键 * @param {Boolean} [config.alt] 是否与 Alt 形成组合键 * @param {Boolean} [config.shift] 是否与 Shift 形成组合键 * */ KeyboardListener.prototype.extendEventType = function extendEventType(config){ var len = 0; if(config instanceof Array){ len = config.length; while(len--){ this._setKeyComposition(config[len]); } } else { this._setKeyComposition(config); } return this; }; /** * @method bind 绑定自定义的键盘事件 * @param {String} type 事件类型 如：['up', 'down', 'left', 'right', 'undo', 'redo', 'delete', zoomIn, 'zoomOut'] * @param {Function} callback 回调函数，参数为一个自定义的仿事件对象 * @param {String} description 对绑定事件的用途进行说明 * */ KeyboardListener.prototype.bind = function bind(type, callback, description){ var allType = this.allEventType; if(allType.indexOf(type) === -1){ throwError('不支持改事件类型，请先扩展该类型，或采用其他事件类型'); } if(!(callback instanceof Function)){ throwError('绑定的事件处理回调必须是函数类型'); } this.callback['on' + type] = callback; this.eventDiscibeSet[type] = description || '没有该事件的描述'; return this; }; /** * @method unbind 解除事件绑定 * @param {String} type 事件类型 * */ KeyboardListener.prototype.unbind = function unbind(type){ this.callback['on' + type] = this._emptyEventHandler; return this; }; }();
总结