mcs/class/referencesource/System.Data/System/Data/Common/SQLTypes/SQLCharsStorage.cs

   1 //------------------------------------------------------------------------------
   2 // <copyright file="SQLCharsStorage.cs" company="Microsoft">
   3 //     Copyright (c) Microsoft Corporation.  All rights reserved.
   4 // </copyright>
   5 // <owner current="true" primary="true">Microsoft</owner>
   6 // <owner current="true" primary="false">Microsoft</owner>
   7 // <owner current="false" primary="false">Microsoft</owner>
   8 //------------------------------------------------------------------------------
   9
  10 namespace System.Data.Common {
  11     using System;
  12     using System.Xml;
  13     using System.IO;
  14     using System.Xml.Serialization;
  15     using System.Data.SqlTypes;
  16     using System.Diagnostics;
  17     using System.Globalization;
  18     using System.Collections;
  19
  20     internal sealed class SqlCharsStorage : DataStorage {
  21
  22         private SqlChars[] values;
  23
  24         public SqlCharsStorage(DataColumn column)
  25         : base(column, typeof(SqlChars), SqlChars.Null, SqlChars.Null, StorageType.SqlChars) {
  26         }
  27
  28         override public Object Aggregate(int[] records, AggregateType kind) {
  29             try {
  30                 switch (kind) {
  31                     case AggregateType.First:
  32                         if (records.Length > 0) {
  33                             return values[records[0]];
  34                         }
  35                         return null;// no data => null
  36
  37                     case AggregateType.Count:
  38                         int count = 0;
  39                         for (int i = 0; i < records.Length; i++) {
  40                             if (!IsNull(records[i]))
  41                                 count++;
  42                         }
  43                         return count;
  44                 }
  45             }
  46             catch (OverflowException) {
  47                 throw ExprException.Overflow(typeof(SqlChars));
  48             }
  49             throw ExceptionBuilder.AggregateException(kind, DataType);
  50         }
  51
  52         override public int Compare(int recordNo1, int recordNo2) {
  53 //            throw ExceptionBuilder.IComparableNotDefined;
  54             return 0;
  55         }
  56
  57         override public int CompareValueTo(int recordNo, Object value) {
  58 //            throw ExceptionBuilder.IComparableNotDefined;
  59             return 0;
  60         }
  61
  62         override public void Copy(int recordNo1, int recordNo2) {
  63             values[recordNo2] = values[recordNo1];
  64         }
  65
  66         override public Object Get(int record) {
  67             return values[record];
  68         }
  69
  70         override public bool IsNull(int record) {
  71             return (values[record].IsNull);
  72         }
  73
  74         override public void Set(int record, Object value) {
  75             if ((value ==  DBNull.Value) || (value == null)){
  76                 values[record] = SqlChars.Null;
  77             }
  78             else {
  79                 values[record] = (SqlChars)value;
  80             }
  81         }
  82
  83         override public void SetCapacity(int capacity) {
  84             SqlChars[] newValues = new SqlChars[capacity];
  85             if (null != values) {
  86                 Array.Copy(values, 0, newValues, 0, Math.Min(capacity, values.Length));
  87             }
  88             values = newValues;
  89         }
  90
  91         override public object ConvertXmlToObject(string s) {
  92             SqlString newValue = new SqlString();
  93
  94             string tempStr =string.Concat("<col>", s, "</col>"); // this is done since you can give fragmet to reader, bug 98767
  95             StringReader strReader = new  StringReader(tempStr);
  96
  97             IXmlSerializable tmp = newValue;
  98
  99             using (XmlTextReader xmlTextReader = new XmlTextReader(strReader)) {
 100                 tmp.ReadXml(xmlTextReader);
 101             }
 102             return (new SqlChars((SqlString)tmp));
 103         }
 104
 105         override public string ConvertObjectToXml(object value) {
 106             Debug.Assert(!DataStorage.IsObjectNull(value), "we shouldn't have null here");
 107             Debug.Assert((value.GetType() == typeof(SqlChars)), "wrong input type");
 108
 109             StringWriter strwriter = new StringWriter(FormatProvider);
 110
 111             using (XmlTextWriter xmlTextWriter = new XmlTextWriter (strwriter)) {
 112                 ((IXmlSerializable)value).WriteXml(xmlTextWriter);
 113             }
 114             return (strwriter.ToString ());
 115         }
 116
 117         override protected object GetEmptyStorage(int recordCount) {
 118             return new SqlChars[recordCount];
 119         }
 120
 121         override protected void CopyValue(int record, object store, BitArray nullbits, int storeIndex) {
 122             SqlChars[] typedStore = (SqlChars[]) store;
 123             typedStore[storeIndex] = values[record];
 124             nullbits.Set(storeIndex, IsNull(record));
 125         }
 126
 127         override protected void SetStorage(object store, BitArray nullbits) {
 128             values = (SqlChars[]) store;
 129             //SetNullStorage(nullbits);
 130         }
 131     }
 132 }