[英]How to create DevExpress XPO dynamically with multiple primary-keys table?
但它僅適用於單個主鍵表。 所以我搜索了更多發現這個: https://github.com/DevExpress-Examples/XPO_how-to-create-persistent-classes-mapped-to-tables-with-a-composite-primary-key-at-runtime-e4606
但是有很大的不同,我認為它不令人滿意,因為它談到了復合鍵(一個有很多列的鍵)所以我需要一個從 SQL 動態創建 XPO 的示例 -Server Table: My Table Schema 如下
然后 XPOCollectionSource 在服務器模式下綁定到網格……這就是我所需要的。
我使用的代碼
XPServerCollectionSource GetServerModeSourceForTable(IDbConnection connection, string tableName) {
XPDictionary dict = new ReflectionDictionary();
XPClassInfo classInfo = dict.CreateClass(dict.QueryClassInfo(typeof(LiteDataObject)),
tableName);
DBTable[] tables = ((ConnectionProviderSql)XpoDefault.GetConnectionProvider(connection,
AutoCreateOption.None)).GetStorageTables(tableName);
foreach (DBColumn col in tables[0].Columns) {
XPMemberInfo member = classInfo.CreateMember(col.Name, DBColumn.GetType(
col.ColumnType));
if (tables[0].PrimaryKey.Columns.Contains(col.Name))
member.AddAttribute(new KeyAttribute());
}
return new XPServerCollectionSource(new Session(XpoDefault.GetDataLayer(
connection, dict, AutoCreateOption.None)), classInfo);
}
乍看上去。 如何將XPServerCollectionSource
與動態創建的 XPO object 一起使用。 有兩個主鍵。
這是必須使用的 class。 誰需要更多細節。 我可以免費幫助他。
實現可以像:
[NonPersistent]
public class XPDynamicObject : XPLiteObject
{
public XPDynamicObject(Session session) : base(session) {}
public XPDynamicObject(Session session, XPClassInfo classInfo) : base(session, classInfo) { }
}
Button_Click or any event :
XPDynamicObject.AutoSaveOnEndEdit = false;
ReflectionDictionary dic = new ReflectionDictionary();
var classInfo = dic.CreateClass(dic.GetClassInfo(typeof(XPDynamicObject)), "general.users");
// WE MUST get schema from database .... via ConnectionProviderSql this is only way
var provider = XpoDefault.GetConnectionProvider(MSSqlConnectionProvider.GetConnectionString("(local)", "testdb"), AutoCreateOption.None) as ConnectionProviderSql;
// Composite Key - this is only way to add composite key dynamically
XPComplexCustomMemberInfo user_key = new
XPComplexCustomMemberInfo(classInfo, "user_key", typeof(object), new KeyAttribute(), new PersistentAttribute(), new BrowsableAttribute(false));
user_key.AddSubMember("user_brn", typeof(int), new PersistentAttribute("user_brn"));
user_key.AddSubMember("user_num", typeof(int), new PersistentAttribute("user_num"));
var user_name = classInfo.CreateMember("user_name", typeof(string));
user_name.AddAttribute(new PersistentAttribute("user_name"));
dal = new SimpleDataLayer(dic, provider);
XPServerCollectionSource xpServerCollectionSource = new XPServerCollectionSource(session, classInfo); // XPServerCollectionSource Only Editable server-mode datasource via ALlowNew, AllowEdit, AllowRemove properties
GridControl.DataSource = xpServerCollectionSource;
要通過鍵或條件搜索 Object,請使用以下命令:
編輯:2021-05-24
對於那些詢問與復合鍵關聯的人。 這真是一場噩夢。 默認情況下,Xpo 不提供。 相反,您可以在子類中使用 Session.GetObjectByKey() 並在父類 class 中使用新的 XPCollection。 但實際上它有點慢,用人工鑰匙的原生方式。
一目了然:使用人工/單鍵列以獲得更好的任何 ORM 兼容性。 否則以后在數據庫中將是一場噩夢。 例如,如果您支持另一個或更換當前的 ORM。
這是與復合鍵關聯的代碼。 (請注意,您需要像上圖那樣動態轉換它。您可能需要創建自定義 XPMemberInfo 並覆蓋 GetValue() 以返回 Session.GetObjectByKey() 並創建新的 XPCollection。(真的很糟糕,最糟糕的事情是不支持曾經由 Xpo。所以復合鍵在技術上是不好的方法,除非你需要創建單個表將其綁定到網格。例如:-沒有更多子表的 SalesOrderDetail 表)
[Persistent("users")]
public class user : XPLiteObject
{
public user(Session session) : base(session) { }
public user(Session session, XPClassInfo classInfo) : base(session, classInfo) { }
[Key, Persistent]
public user_key user_key { get; set; }
[Persistent("user_name")]
public string user_name { get; set; }
private XPCollection<Trans> _trans;
public XPCollection<Trans> trans
{
get
{
if (_trans == null)
_trans = new XPCollection<Trans>(Session, CriteriaOperator.Parse($"user_brn = {user_key.user_brn} AND user_num = {user_key.user_num}"));
return _trans;
}
}
}
public class Trans : XPLiteObject
{
public Trans(Session session) : base(session) { }
public Trans(Session session, XPClassInfo classInfo) : base(session, classInfo) { }
[Key,Persistent("TransID")]
public int TransID { get; set; }
public int user_brn { get; set; }
public int user_num { get; set; }
public user user
{
get
{
var key = new user_key();
key.user_brn = 1;
key.user_num = 3;
var obj = Session.GetObjectByKey<user>(key, true);
return obj;
}
}
}
// Composite-Key
public struct user_key
{
[Persistent("user_brn")]
public int user_brn { get; set; }
[Persistent("user_num")]
public int user_num { get; set; }
}
model 以上的動態運行時版本:
class XPCompositeAssociationMemberInfo : XPCustomMemberInfo
{
public XPCompositeAssociationMemberInfo(XPClassInfo owner, string propertyName, Type propertyType, XPClassInfo referenceType, bool nonPersistent, bool nonPublic) : base(owner, propertyName, propertyType, referenceType, nonPersistent, nonPublic)
{
}
public override object GetValue(object theObject)
{
XPDynamicObject val = theObject as XPDynamicObject;
if(val != null)
{
var user_num = val.GetMemberValue("user_num");
IdList vals = new IdList();
vals.Add(1);
vals.Add(user_num);
return val.Session.GetObjectByKey(ReferenceType, vals);
}
return val;
}
}
XPDynamicObject.AutoSaveOnEndEdit = false;
ReflectionDictionary dic = new ReflectionDictionary();
var userClassInfo = dic.CreateClass(dic.GetClassInfo(typeof(XPDynamicObject)), "users");
// WE MUST get schema from database .... via ConnectionProviderSql this is only way
var provider = XpoDefault.GetConnectionProvider(MSSqlConnectionProvider.GetConnectionString("(local)", "testdb"), AutoCreateOption.None) as ConnectionProviderSql;
//DBTable Table = provider.GetStorageTables("users")[0];
// Composite Key - this is only way to add composite key dynamically
XPComplexCustomMemberInfo user_key = new XPComplexCustomMemberInfo(userClassInfo, "user_key", typeof(object), new KeyAttribute(), new PersistentAttribute(), new BrowsableAttribute(false));
user_key.AddSubMember("user_brn", typeof(int), new PersistentAttribute("user_brn"));
user_key.AddSubMember("user_num", typeof(int), new PersistentAttribute("user_num"));
var user_name = userClassInfo.CreateMember("user_name", typeof(string));
user_name.AddAttribute(new PersistentAttribute("user_name"));
var transClassInfo = dic.CreateClass(dic.GetClassInfo(typeof(XPDynamicObject)), "Trans");
var TransID = transClassInfo.CreateMember("TransID", typeof(int), new KeyAttribute());
var user_brn = transClassInfo.CreateMember("user_brn", typeof(int));
var user_num = transClassInfo.CreateMember("user_num", typeof(int));
XPCompositeAssociationMemberInfo userMI = new XPCompositeAssociationMemberInfo(transClassInfo, "user", typeof(object), userClassInfo, true, false);
dal = new SimpleDataLayer(dic, provider);
Session session = new Session(dal);
XPServerCollectionSource xpServerCollectionSource = new XPServerCollectionSource(session, transClassInfo); // XPServerCollectionSource Only Editable server-mode datasource via ALlowNew, AllowEdit, AllowRemove properties
xpServerCollectionSource.DisplayableProperties = "TransID;user.user_key.user_num;user.user_name";
最后,重要!
在任何 Xpo 中運行時實現 Composite-Keys 案例真的非常非常困難。 而是替換為單列鍵(身份或人工。GUID 等)
我不知道這是否是您想要的,但我將使用XPInstantFeedbackSource
分享我的代碼。
您可以在如何實施即時反饋模式 Xpo中獲得更多信息
XPLiteObject
LogXPOModel[Persistent("log.t_log")]
public class LogXPOModel : XPLiteObject
{
[Key, DevExpress.Xpo.DisplayName("id")]
public long id { get; set; }
[Key, DevExpress.Xpo.DisplayName("recv_time")]
public long recv_time
...
}
Window
主窗口public class MainWindow : Window
{
public XPInstantFeedbackSource SqliteXPInstantFeedbackSource
public MainWindow() {
...
SqliteXPInstantFeedbackSource = new XPInstantFeedbackSource();
SqliteXPInstantFeedbackSource.ObjectType = typeof(LogXPOModel);
SqliteXPInstantFeedbackSource.ResolveSession += SqliteXPInstantFeedbackSource_ResolveSession;
SqliteXPInstantFeedbackSource.DismissSession += SqliteXPInstantFeedbackSource_DismissSession;
View.Grid.ItemsSource = SqliteXPInstantFeedbackSource;
}
...
}
就像那樣——我的桌子有兩個鑰匙; 並且,它不會產生任何問題。
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