textfield添加 事件 监听 捕捉TextField的即时变化

	var companyNameField = new Ext.form.TextField({
            fieldLabel: '公司名称',
            name: 'member',
            emptyText:'输入查询公司名称的关键词...',
            allowBlank:true,
            enableKeyEvents: true,  
			initEvents: function() {  
		    var keyUp = function(e){  
		    	if(companyStore != undefined) companyStore.filter('companyName', this.getValue(), true);
		    };  
		    this.el.on("keyup", keyUp, this);  
		} ,
            anchor:'95%'
		});