private static void SetText(DataContext db, Type tableType, ItemNavigator itemNavigator)
{
ParameterExpression param = Expression.Parameter(tableType, "c");
Expression right = Expression.Constant(itemNavigator.ValueNullable.Value);
Expression left = Expression.Property(param, tableType.GetProperty("id"));
Expression filter = Expression.Equal(left, right);
Expression pred = Expression.Lambda(filter, param);
ITable table = db.GetTable(tableType);
Expression expr = Expression.Call(typeof(Queryable), "Where", new[] { tableType },
Expression.Constant(table), pred);
IQueryable query = table.AsQueryable().Provider.CreateQuery(expr);
IEnumerator enumerator = query.GetEnumerator();
if (!enumerator.MoveNext())
{
itemNavigator.Text = "[запись не найдена]";
return;
}
var obj = enumerator.Current;
itemNavigator.Text = GetText(obj, itemNavigator.ColumnName);
if (!string.IsNullOrEmpty(itemNavigator.AlternativeColumnName))
{
itemNavigator.AlternativeText = GetText(obj, itemNavigator.AlternativeColumnName);
}
}
public void LINQ_orderby_int()
{
var q = from r in table.AsQueryable()
orderby r.IntProp
select r;
var l = q.ToList();
Assert.AreEqual(2, l.Count);
Assert.AreEqual(e1.IntProp, l[0].IntProp);
Assert.AreEqual(e2.IntProp, l[1].IntProp);
}
public static IUpdatable <JoinHelper <T, T> > BuildBulkUpdate <T>(
DataConnection dataConnection,
ITable <T> target,
ITable <T> sourceTable,
params Expression <Func <T, object> >[] fields
) where T : class
{
var descriptor = dataConnection.MappingSchema.GetEntityDescriptor(typeof(T));
var members = new List <MemberInfo>();
if (fields.Length == 0)
{
members.AddRange(
descriptor.Columns
.Where(c => !c.SkipOnUpdate & !c.IsPrimaryKey & !c.IsIdentity)
.Select(c => c.MemberInfo)
);
}
else
{
foreach (var field in fields)
{
var member = MemberHelper.GetMemberInfo(field);
if (member == null)
{
throw new LinqToDBException($"Can not retrive member info from lambda function: {field}");
}
members.Add(member);
}
}
/* Emulating the following calls
*
* var join = target.InnerJoin(temporaryTable, (outer, inner) => outer.ID1 == inner.ID1 && outer.ID2 == inner.ID2,
* (outer, inner) => new DynamicExtensions.JoinHelper<BulkUpdateEntity, BulkUpdateEntity>
* {
* Outer = outer,
* Inner = inner
* });
*
* var updatable = join.AsUpdatable();
* updatable = updatable.Set(pair => pair.Outer.Value1, pair => pair.Inner.Value1);
* updatable = updatable.Set(pair => pair.Outer.Value2, pair => pair.Inner.Value2);
*/
var joinMethod = InnerJoinMethodInfo.MakeGenericMethod(typeof(T), typeof(T), typeof(JoinHelper <T, T>));
var outerParam = Expression.Parameter(typeof(T), "outer");
var innerParam = Expression.Parameter(typeof(T), "inner");
Expression cmpExpression = null;
foreach (var c in descriptor.Columns.Where(c => c.IsPrimaryKey))
{
var equals = Expression.Equal(
Expression.MakeMemberAccess(outerParam, c.MemberInfo),
Expression.MakeMemberAccess(innerParam, c.MemberInfo)
);
cmpExpression = cmpExpression == null ? equals : Expression.AndAlso(cmpExpression, equals);
}
if (cmpExpression == null)
{
throw new LinqToDBException($"Entity {typeof(T)} does not contain primary key");
}
var equalityLambda = Expression.Lambda(cmpExpression, outerParam, innerParam);
var helperType = typeof(JoinHelper <T, T>);
var constructor = helperType.GetConstructor(new Type[0]);
var joinHelperOuterPropertyInfo = helperType.GetProperty("Outer");
var joinHelperInnerPropertyInfo = helperType.GetProperty("Inner");
var newExpression =
Expression.Lambda(
Expression.MemberInit(
Expression.New(constructor),
Expression.Bind(joinHelperOuterPropertyInfo, outerParam),
Expression.Bind(joinHelperInnerPropertyInfo, innerParam)
),
outerParam,
innerParam);
var joinQuery = joinMethod.Invoke(null, new object[] { target.AsQueryable(), sourceTable.AsQueryable(), equalityLambda, newExpression });
object updatable = ((IQueryable <JoinHelper <T, T> >)joinQuery).AsUpdatable();
var helperParam = Expression.Parameter(helperType, "pair");
var outerExpression = Expression.MakeMemberAccess(helperParam, joinHelperOuterPropertyInfo);
var innerExpression = Expression.MakeMemberAccess(helperParam, joinHelperInnerPropertyInfo);
foreach (var memberInfo in members)
{
var method = SetExpressionMethodInfo.MakeGenericMethod(helperType, memberInfo.GetMemberType());
var propLambda = Expression.Lambda(Expression.MakeMemberAccess(outerExpression, memberInfo), helperParam);
var valueLambda = Expression.Lambda(Expression.MakeMemberAccess(innerExpression, memberInfo), helperParam);
updatable = method.Invoke(null, new object[] { updatable, propLambda, valueLambda });
}
return((IUpdatable <JoinHelper <T, T> >)updatable);
}
