mco_uda_unregister_event_handler

原型

    MCO_RET mco_uda_unregister_event_handler(	/*IN*/ mco_trans_h t, 
                            /*IN*/ unsigned short struct_no, 
                            /*IN*/ unsigned short event_no,
                            /*IN*/ mco_uda_event_handler  handler );

参数

t	事务处理
struct_no	结构/类编号（必须介于 0 和 - 1 之间）mco_dict_struct_count()
event_no	事件编号
handler	函数实现的名称mco_uda_event_handler

描述

取消注册之前向 注册的特定事件的事件处理程序。mco_uda_register_event_handler()

返回

MCO_S_OK	处理程序已成功取消注册
MCO_ERR_UDA	取消注册处理程序的致命错误

示例

    /*  应用程序代码片段 */
        
     
    MCO_RET sync_event_handler(mco_trans_h t, mco_uda_object_handle_p obj, const mco_dict_event_info_t *event_info, void *param)
    {
        mco_dict_struct_info_t struct_info;
        mco_dict_field_info_t field_info;
        mco_uda_value_t val;
        autoid_t obj_autoid;
         
        mco_dict_struct(metadict, 0, obj->struct_no, &struct_info);
        mco_dict_field_name(metadict, 0, obj->struct_no, "autoid", &field_info);
        val.type = MCO_DD_AUTOID;
        mco_uda_get(obj, field_info.field_no, 0, &val);
        obj_autoid = val.v.u8;
         
        if (event_info->type == MCO_EVENT_UPDATE || event_info->type == MCO_EVENT_CLASS_UPDATE) 
        {
            mco_dict_field(metadict, 0, obj->struct_no, event_info->field_no, &field_info);
            printf("Sync. event for obj %" INT8_FORMAT "d: class %s, event_no=%d, type=UPDATE, when=%s, field=%s, value=",
            obj_autoid, struct_info.name, event_info->event_no, ((int)param == MCO_AFTER_UPDATE) ? "AFTER" : "BEFORE", field_info.name);
             
            print_obj_field(obj, &field_info);
        } else {
            printf("Sync. event for obj %" INT8_FORMAT "d: class %s, event_no=%d, type=", obj_autoid, struct_info.name, event_info->event_no);
            switch (event_info->type) {
                case MCO_EVENT_NEW        : printf("NEW"); break;
                case MCO_EVENT_DELETE     : printf("DELETE"); break;
                case MCO_EVENT_DELETE_ALL : printf("DELETE_ALL"); break;
                case MCO_EVENT_CHECKPOINT : printf("CHECKPOINT"); break;
                default                   : printf("UNKNOWN"); dbg_exit(1);
            }
        }
        printf("\n");
        return MCO_S_OK;
    }
     
    void unregister_sync_events(mco_trans_h t)
    {
        unsigned short struct_count, s, e;
        mco_dict_struct_info_t struct_info;
        mco_dict_event_info_t event_info;
         
        mco_dict_struct_count(metadict, 0, &struct_count);
        for (s = 0; s < struct_count; ++s) {
            mco_dict_struct(metadict, 0, s, &struct_info);
            for (e = 0; e < struct_info.event_count; ++e) {
                mco_dict_event(metadict, 0, s, e, &event_info);
                if (event_info.type == MCO_EVENT_UPDATE) {
                    mco_uda_unregister_event_handler(t, s, e, &sync_event_handler);
                }
                mco_uda_unregister_event_handler(t, s, e, &sync_event_handler);
        
            }
        }
    }
     
     
    int main(int argc, char* argv[])
    {
        MCO_RET rc;
        mco_db_h db;
        mco_trans_h t;
        ...
         
        mco_trans_start(db, MCO_READ_WRITE, MCO_TRANS_FOREGROUND, &t);
        unregister_sync_events(t);
        mco_trans_commit(t);
        ...
    }