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//------------------------------------------------------------------------------
// <copyright file="StringStorage.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
// <owner current="true" primary="true">Microsoft</owner>
// <owner current="true" primary="false">Microsoft</owner>
// <owner current="false" primary="false">Microsoft</owner>
//------------------------------------------------------------------------------
namespace System.Data.Common {
using System;
using System.Diagnostics;
using System.Globalization;
using System.Data.SqlTypes;
using System.Collections;
// The string storage does not use BitArrays in DataStorage
internal sealed class StringStorage : DataStorage {
private String[] values;
public StringStorage(DataColumn column)
: base(column, typeof(String), String.Empty, StorageType.String) {
}
override public 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+1; 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+1; 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);
}
override public int Compare(int recordNo1, int recordNo2) {
string valueNo1 = values[recordNo1];
string valueNo2 = values[recordNo2];
if ((Object)valueNo1 == (Object)valueNo2)
return 0;
if (valueNo1 == null)
return -1;
if (valueNo2 == null)
return 1;
return Table.Compare(valueNo1, valueNo2);
}
override public 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;
}
override public void Copy(int recordNo1, int recordNo2) {
values[recordNo2] = values[recordNo1];
}
override public Object Get(int recordNo) {
String value = values[recordNo];
if (null != value) {
return value;
}
return NullValue;
}
override public int GetStringLength(int record) {
string value = values[record];
return ((null != value) ? value.Length : 0);
}
override public bool IsNull(int record) {
return (null == values[record]);
}
override public void Set(int record, Object value) {
System.Diagnostics.Debug.Assert(null != value, "null value");
if (NullValue == value) {
values[record] = null;
}
else {
values[record] = value.ToString();
}
}
override public void SetCapacity(int capacity) {
string[] newValues = new string[capacity];
if (values != null) {
Array.Copy(values, 0, newValues, 0, Math.Min(capacity, values.Length));
}
values = newValues;
}
override public object ConvertXmlToObject(string s) {
return s;
}
override public string ConvertObjectToXml(object value) {
return (string)value;
}
override protected object GetEmptyStorage(int recordCount) {
return new String[recordCount];
}
override protected void CopyValue(int record, object store, BitArray nullbits, int storeIndex) {
String[] typedStore = (String[]) store;
typedStore[storeIndex] = values[record];
nullbits.Set(storeIndex, IsNull(record));
}
override protected void SetStorage(object store, BitArray nullbits) {
values = (String[]) store;
// SetNullStorage(nullbits);
}
}
}
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