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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
using System.Collections;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
namespace System.Data.Common
{
// The string storage does not use BitArrays in DataStorage
internal sealed class StringStorage : DataStorage
{
private string?[] _values = default!; // Late-initialized
public StringStorage(DataColumn column)
: base(column, typeof(string), string.Empty, StorageType.String)
{
}
public override object Aggregate(int[] recordNos, AggregateType kind)
{
int i;
switch (kind)
{
case AggregateType.Min:
int min = -1;
for (i = 0; i < recordNos.Length; i++)
{
if (IsNull(recordNos[i]))
continue;
min = recordNos[i];
break;
}
if (min >= 0)
{
for (i++; i < recordNos.Length; i++)
{
if (IsNull(recordNos[i]))
continue;
if (Compare(min, recordNos[i]) > 0)
{
min = recordNos[i];
}
}
return Get(min);
}
return _nullValue;
case AggregateType.Max:
int max = -1;
for (i = 0; i < recordNos.Length; i++)
{
if (IsNull(recordNos[i]))
continue;
max = recordNos[i];
break;
}
if (max >= 0)
{
for (i++; i < recordNos.Length; i++)
{
if (Compare(max, recordNos[i]) < 0)
{
max = recordNos[i];
}
}
return Get(max);
}
return _nullValue;
case AggregateType.Count:
int count = 0;
for (i = 0; i < recordNos.Length; i++)
{
object? value = _values[recordNos[i]];
if (value != null)
count++;
}
return count;
}
throw ExceptionBuilder.AggregateException(kind, _dataType);
}
public override int Compare(int recordNo1, int recordNo2)
{
string? valueNo1 = _values[recordNo1];
string? valueNo2 = _values[recordNo2];
if (valueNo1 == (object?)valueNo2)
return 0;
if (valueNo1 == null)
return -1;
if (valueNo2 == null)
return 1;
return _table.Compare(valueNo1, valueNo2);
}
public override int CompareValueTo(int recordNo, object? value)
{
Debug.Assert(recordNo != -1, "Invalid (-1) parameter: 'recordNo'");
Debug.Assert(null != value, "null value");
string? valueNo1 = _values[recordNo];
if (null == valueNo1)
{
if (_nullValue == value)
{
return 0;
}
else
{
return -1;
}
}
else if (_nullValue == value)
{
return 1;
}
return _table.Compare(valueNo1, (string)value);
}
public override object ConvertValue(object? value)
{
if (_nullValue != value)
{
if (null != value)
{
value = value.ToString()!;
}
else
{
value = _nullValue;
}
}
return value;
}
public override void Copy(int recordNo1, int recordNo2)
{
_values[recordNo2] = _values[recordNo1];
}
public override object Get(int recordNo)
{
string? value = _values[recordNo];
if (null != value)
{
return value;
}
return _nullValue;
}
public override int GetStringLength(int record)
{
string? value = _values[record];
return ((null != value) ? value.Length : 0);
}
public override bool IsNull(int record)
{
return (null == _values[record]);
}
public override void Set(int record, object value)
{
Debug.Assert(null != value, "null value");
if (_nullValue == value)
{
_values[record] = null;
}
else
{
_values[record] = value.ToString();
}
}
public override void SetCapacity(int capacity)
{
string[] newValues = new string[capacity];
if (_values != null)
{
Array.Copy(_values, newValues, Math.Min(capacity, _values.Length));
}
_values = newValues;
}
[RequiresUnreferencedCode(DataSet.RequiresUnreferencedCodeMessage)]
public override object ConvertXmlToObject(string s)
{
return s;
}
[RequiresUnreferencedCode(DataSet.RequiresUnreferencedCodeMessage)]
public override string ConvertObjectToXml(object value)
{
return (string)value;
}
protected override object GetEmptyStorage(int recordCount)
{
return new string[recordCount];
}
protected override void CopyValue(int record, object store, BitArray nullbits, int storeIndex)
{
string?[] typedStore = (string?[])store;
typedStore[storeIndex] = _values[record];
nullbits.Set(storeIndex, IsNull(record));
}
protected override void SetStorage(object store, BitArray nullbits)
{
_values = (string?[])store;
// SetNullStorage(nullbits);
}
}
}
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