Code:
/ FX-1434 / FX-1434 / 1.0 / untmp / whidbey / REDBITS / ndp / fx / src / Data / System / Data / Common / Int16Storage.cs / 1 / Int16Storage.cs
//------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //[....] //[....] //[....] //----------------------------------------------------------------------------- namespace System.Data.Common { using System; using System.Xml; using System.Data.SqlTypes; using System.Collections; internal sealed class Int16Storage : DataStorage { private const Int16 defaultValue = 0; private Int16[] values; internal Int16Storage(DataColumn column) : base(column, typeof(Int16), defaultValue) { } override public Object Aggregate(int[] records, AggregateType kind) { bool hasData = false; try { switch (kind) { case AggregateType.Sum: Int64 sum = defaultValue; foreach (int record in records) { if (HasValue(record)) { checked { sum += values[record];} hasData = true; } } if (hasData) { return sum; } return NullValue; case AggregateType.Mean: Int64 meanSum = (Int64)defaultValue; int meanCount = 0; foreach (int record in records) { if (HasValue(record)) { checked { meanSum += (Int64)values[record];} meanCount++; hasData = true; } } if (hasData) { Int16 mean; checked {mean = (Int16)(meanSum / meanCount);} return mean; } return NullValue; case AggregateType.Var: case AggregateType.StDev: int count = 0; double var = 0.0f; double prec = 0.0f; double dsum = 0.0f; double sqrsum = 0.0f; foreach (int record in records) { if (HasValue(record)) { dsum += (double)values[record]; sqrsum += (double)values[record]*(double)values[record]; count++; } } if (count > 1) { var = ((double)count * sqrsum - (dsum * dsum)); prec = var / (dsum * dsum); // we are dealing with the risk of a cancellation error // double is guaranteed only for 15 digits so a difference // with a result less than 1e-15 should be considered as zero if ((prec < 1e-15) || (var <0)) var = 0; else var = var / (count * (count -1)); if (kind == AggregateType.StDev) { return Math.Sqrt(var); } return var; } return NullValue; case AggregateType.Min: Int16 min = Int16.MaxValue; for (int i = 0; i < records.Length; i++) { int record = records[i]; if (HasValue(record)) { min=Math.Min(values[record], min); hasData = true; } } if (hasData) { return min; } return NullValue; case AggregateType.Max: Int16 max = Int16.MinValue; for (int i = 0; i < records.Length; i++) { int record = records[i]; if (HasValue(record)) { max=Math.Max(values[record], max); hasData = true; } } if (hasData) { return max; } return NullValue; case AggregateType.First: if (records.Length > 0) { return values[records[0]]; } return null; case AggregateType.Count: count = 0; for (int i = 0; i < records.Length; i++) { if (HasValue(records[i])) { count++; } } return count; } } catch (OverflowException) { throw ExprException.Overflow(typeof(Int16)); } throw ExceptionBuilder.AggregateException(kind, DataType); } override public int Compare(int recordNo1, int recordNo2) { Int16 valueNo1 = values[recordNo1]; Int16 valueNo2 = values[recordNo2]; if (valueNo1 == defaultValue || valueNo2 == defaultValue) { int bitCheck = CompareBits(recordNo1, recordNo2); if (0 != bitCheck) { return bitCheck; } } //return valueNo1.CompareTo(valueNo2); return(valueNo1 - valueNo2); // copied from Int16.CompareTo(Int16) } public override int CompareValueTo(int recordNo, object value) { System.Diagnostics.Debug.Assert(0 <= recordNo, "Invalid record"); System.Diagnostics.Debug.Assert(null != value, "null value"); if (NullValue == value) { return (HasValue(recordNo) ? 1 : 0); } Int16 valueNo1 = values[recordNo]; if ((defaultValue == valueNo1) && !HasValue(recordNo)) { return -1; } return valueNo1.CompareTo((Int16)value); //return(valueNo1 - valueNo2); // copied from Int16.CompareTo(Int16) } public override object ConvertValue(object value) { if (NullValue != value) { if (null != value) { value = ((IConvertible)value).ToInt16(FormatProvider); } else { value = NullValue; } } return value; } override public void Copy(int recordNo1, int recordNo2) { CopyBits(recordNo1, recordNo2); values[recordNo2] = values[recordNo1]; } override public Object Get(int record) { Int16 value = values[record]; if (value != defaultValue) { return value; } return GetBits(record); } override public void Set(int record, Object value) { System.Diagnostics.Debug.Assert(null != value, "null value"); if (NullValue == value) { values[record] = defaultValue; SetNullBit(record, true); } else { values[record] = ((IConvertible)value).ToInt16(FormatProvider); SetNullBit(record, false); } } override public void SetCapacity(int capacity) { Int16[] newValues = new Int16[capacity]; if (null != values) { Array.Copy(values, 0, newValues, 0, Math.Min(capacity, values.Length)); } values = newValues; base.SetCapacity(capacity); } override public object ConvertXmlToObject(string s) { return XmlConvert.ToInt16(s); } override public string ConvertObjectToXml(object value) { return XmlConvert.ToString((Int16) value); } override protected object GetEmptyStorage(int recordCount) { return new Int16[recordCount]; } override protected void CopyValue(int record, object store, BitArray nullbits, int storeIndex) { Int16[] typedStore = (Int16[]) store; typedStore[storeIndex] = values[record]; nullbits.Set(storeIndex, !HasValue(record)); } override protected void SetStorage(object store, BitArray nullbits) { values = (Int16[]) store; SetNullStorage(nullbits); } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved.
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- WebBrowserBase.cs
- XMLDiffLoader.cs
- ReversePositionQuery.cs
- DataSetMappper.cs
- UserControlBuildProvider.cs
- XmlSchemaComplexType.cs
- PropertyDescriptor.cs
- HwndTarget.cs
- StandardBindingOptionalReliableSessionElement.cs
- WindowsListBox.cs
- SHA384Managed.cs
- FormDocumentDesigner.cs
- HandleCollector.cs
- HttpWriter.cs
- AmbientLight.cs
- MetafileHeaderEmf.cs
- CommandLineParser.cs
- DataListCommandEventArgs.cs
- GroupBox.cs
- RelationshipFixer.cs
- Rect.cs
- SqlProviderServices.cs
- DrawingContextWalker.cs
- EventTrigger.cs
- ObjectKeyFrameCollection.cs
- NavigationExpr.cs
- CreateSequence.cs
- TagPrefixCollection.cs
- FamilyCollection.cs
- MachineKeyConverter.cs
- AssertSection.cs
- MetadataUtil.cs
- GridItemCollection.cs
- HttpRuntime.cs
- SoundPlayer.cs
- ClipboardData.cs
- SiteMapDataSource.cs
- XmlSchemaExternal.cs
- CalendarButtonAutomationPeer.cs
- EventLog.cs
- _UncName.cs
- PiiTraceSource.cs
- PrimitiveCodeDomSerializer.cs
- SortQueryOperator.cs
- DTCTransactionManager.cs
- SettingsPropertyCollection.cs
- DesignObjectWrapper.cs
- XmlNullResolver.cs
- CellConstant.cs
- ClientRuntimeConfig.cs
- TemplatePartAttribute.cs
- HttpsHostedTransportConfiguration.cs
- UrlPath.cs
- SafeHandles.cs
- webeventbuffer.cs
- KnownTypes.cs
- DataGridViewImageCell.cs
- ScaleTransform3D.cs
- LayoutSettings.cs
- SQLUtility.cs
- CounterCreationData.cs
- ListDesigner.cs
- EntityDataSourceWrapperPropertyDescriptor.cs
- LocationReferenceValue.cs
- Highlights.cs
- NoClickablePointException.cs
- Interlocked.cs
- CorrelationManager.cs
- TabPage.cs
- SqlVersion.cs
- BindValidationContext.cs
- ObjectPropertyMapping.cs
- SrgsOneOf.cs
- SymbolTable.cs
- TypographyProperties.cs
- Deflater.cs
- NodeCounter.cs
- RegistrationServices.cs
- TextTreeUndoUnit.cs
- FacetDescriptionElement.cs
- BitmapEffectDrawingContextState.cs
- EntityModelBuildProvider.cs
- SqlServer2KCompatibilityCheck.cs
- XmlEventCache.cs
- XmlILAnnotation.cs
- XMLUtil.cs
- URI.cs
- XmlHelper.cs
- ListBoxItemAutomationPeer.cs
- ExpressionLink.cs
- IndexOutOfRangeException.cs
- PointAnimationUsingPath.cs
- ProviderUtil.cs
- PhysicalOps.cs
- JsonQNameDataContract.cs
- XmlSchemas.cs
- DeclarativeCatalogPart.cs
- NetPeerTcpBinding.cs
- DBSchemaRow.cs
- StatusBarItem.cs