ext js 鼠标事件

listeners:{
                                'blur' : function(){
                                     var str = Ext.get('roleListaddname').dom.value;
                                     var roleName = str.indexOf('_')+1;
                                     var sub_name = str.substring(0, roleName);
                                     if(sub_name != 'ROLE_'){
                                     str = 'ROLE_'+ str;
                                     Ext.get('roleListaddname').dom.value = str;
                                     }
                                     if(sub_name == 'role_'){
                                     var r_name = str.substring(str.lastIndexOf('_')+1, str.length);
                                     Ext.get('roleListaddname').dom.value = sub_name.toUpperCase() + r_name;
                                     }
                                }
                                     }