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//------------------------------------------------------------------------------
// <copyright file="SQLBinary.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
// <owner current="true" primary="true">junfang</owner>
// <owner current="true" primary="false">Microsoft</owner>
// <owner current="true" primary="false">Microsoft</owner>
//------------------------------------------------------------------------------
//**************************************************************************
// @File: SqlBinary.cs
//
// Create by: JunFang
//
// Purpose: Implementation of SqlBinary which is corresponding to
// data type "binary/varbinary" in SQL Server
//
// Notes:
//
// History:
//
// 1/30/2000 JunFang Created and implemented as first drop.
//
// @EndHeader@
//**************************************************************************
using System;
using System.Data.Common;
using System.Globalization;
using System.Xml;
using System.Xml.Schema;
using System.Xml.Serialization;
namespace System.Data.SqlTypes {
[Serializable]
[XmlSchemaProvider("GetXsdType")]
public struct SqlBinary : INullable, IComparable, IXmlSerializable {
private byte[] m_value; // null if m_value is null
// constructor
// construct a Null
private SqlBinary(bool fNull) {
m_value = null;
}
/// <devdoc>
/// <para>
/// Initializes a new instance of the <see cref='System.Data.SqlTypes.SqlBinary'/> class with a binary object to be stored.
/// </para>
/// </devdoc>
public SqlBinary(byte[] value) {
// if value is null, this generates a SqlBinary.Null
if (value == null)
m_value = null;
else {
m_value = new byte[value.Length];
value.CopyTo(m_value, 0);
}
}
/// <devdoc>
/// <para>
/// Initializes a new instance of the <see cref='System.Data.SqlTypes.SqlBinary'/> class with a binary object to be stored. This constructor will not copy the value.
/// </para>
/// </devdoc>
internal SqlBinary(byte[] value, bool ignored) {
// if value is null, this generates a SqlBinary.Null
if (value == null)
m_value = null;
else {
m_value = value;
}
}
// INullable
/// <devdoc>
/// <para>
/// Gets whether or not <see cref='System.Data.SqlTypes.SqlBinary.Value'/> is null.
/// </para>
/// </devdoc>
public bool IsNull {
get { return(m_value == null);}
}
// property: Value
/// <devdoc>
/// <para>
/// Gets
/// or sets the
/// value of the SQL binary object retrieved.
/// </para>
/// </devdoc>
public byte[] Value {
get {
if (IsNull)
throw new SqlNullValueException();
else {
byte[] value = new byte[m_value.Length];
m_value.CopyTo(value, 0);
return value;
}
}
}
// class indexer
public byte this[int index] {
get {
if (IsNull)
throw new SqlNullValueException();
else
return m_value[index];
}
}
// property: Length
/// <devdoc>
/// <para>
/// Gets the length in bytes of <see cref='System.Data.SqlTypes.SqlBinary.Value'/>.
/// </para>
/// </devdoc>
public int Length {
get {
if (!IsNull)
return m_value.Length;
else
throw new SqlNullValueException();
}
}
// Implicit conversion from byte[] to SqlBinary
// Alternative: constructor SqlBinary(bytep[])
/// <devdoc>
/// <para>
/// Converts a binary object to a <see cref='System.Data.SqlTypes.SqlBinary'/>.
/// </para>
/// </devdoc>
public static implicit operator SqlBinary(byte[] x) {
return new SqlBinary(x);
}
// Explicit conversion from SqlBinary to byte[]. Throw exception if x is Null.
// Alternative: Value property
/// <devdoc>
/// <para>
/// Converts a <see cref='System.Data.SqlTypes.SqlBinary'/> to a binary object.
/// </para>
/// </devdoc>
public static explicit operator byte[](SqlBinary x) {
return x.Value;
}
/// <devdoc>
/// <para>
/// Returns a string describing a <see cref='System.Data.SqlTypes.SqlBinary'/> object.
/// </para>
/// </devdoc>
public override String ToString() {
return IsNull ? SQLResource.NullString : "SqlBinary(" + m_value.Length.ToString(CultureInfo.InvariantCulture) + ")";
}
// Unary operators
// Binary operators
// Arithmetic operators
/// <devdoc>
/// <para>
/// Adds two instances of <see cref='System.Data.SqlTypes.SqlBinary'/> together.
/// </para>
/// </devdoc>
// Alternative method: SqlBinary.Concat
public static SqlBinary operator +(SqlBinary x, SqlBinary y) {
if (x.IsNull || y.IsNull)
return Null;
byte[] rgbResult = new byte[x.Value.Length + y.Value.Length];
x.Value.CopyTo(rgbResult, 0);
y.Value.CopyTo(rgbResult, x.Value.Length);
return new SqlBinary(rgbResult);
}
// Comparisons
private static EComparison PerformCompareByte(byte[] x, byte[] y) {
// the smaller length of two arrays
int len = (x.Length < y.Length) ? x.Length : y.Length;
int i;
for (i = 0; i < len; ++i) {
if (x[i] != y[i]) {
if (x[i] < y[i])
return EComparison.LT;
else
return EComparison.GT;
}
}
if (x.Length == y.Length)
return EComparison.EQ;
else {
// if the remaining bytes are all zeroes, they are still equal.
byte bZero = (byte)0;
if (x.Length < y.Length) {
// array X is shorter
for (i = len; i < y.Length; ++i) {
if (y[i] != bZero)
return EComparison.LT;
}
}
else {
// array Y is shorter
for (i = len; i < x.Length; ++i) {
if (x[i] != bZero)
return EComparison.GT;
}
}
return EComparison.EQ;
}
}
// Implicit conversions
// Explicit conversions
// Explicit conversion from SqlGuid to SqlBinary
/// <devdoc>
/// <para>
/// Converts a <see cref='System.Data.SqlTypes.SqlGuid'/> to a <see cref='System.Data.SqlTypes.SqlBinary'/>
/// .
/// </para>
/// </devdoc>
// Alternative method: SqlGuid.ToSqlBinary
public static explicit operator SqlBinary(SqlGuid x) {
return x.IsNull ? SqlBinary.Null : new SqlBinary(x.ToByteArray());
}
// Builtin functions
// Overloading comparison operators
/// <devdoc>
/// <para>
/// Compares two instances of <see cref='System.Data.SqlTypes.SqlBinary'/> for
/// equality.
/// </para>
/// </devdoc>
public static SqlBoolean operator==(SqlBinary x, SqlBinary y) {
if (x.IsNull || y.IsNull)
return SqlBoolean.Null;
return new SqlBoolean(PerformCompareByte(x.Value, y.Value) == EComparison.EQ);
}
/// <devdoc>
/// <para>
/// Compares two instances of <see cref='System.Data.SqlTypes.SqlBinary'/>
/// for equality.
/// </para>
/// </devdoc>
public static SqlBoolean operator!=(SqlBinary x, SqlBinary y) {
return ! (x == y);
}
/// <devdoc>
/// <para>
/// Compares the first <see cref='System.Data.SqlTypes.SqlBinary'/> for being less than the
/// second <see cref='System.Data.SqlTypes.SqlBinary'/>.
/// </para>
/// </devdoc>
public static SqlBoolean operator<(SqlBinary x, SqlBinary y) {
if (x.IsNull || y.IsNull)
return SqlBoolean.Null;
return new SqlBoolean(PerformCompareByte(x.Value, y.Value) == EComparison.LT);
}
/// <devdoc>
/// <para>
/// Compares the first <see cref='System.Data.SqlTypes.SqlBinary'/> for being greater than the second <see cref='System.Data.SqlTypes.SqlBinary'/>.
/// </para>
/// </devdoc>
public static SqlBoolean operator>(SqlBinary x, SqlBinary y) {
if (x.IsNull || y.IsNull)
return SqlBoolean.Null;
return new SqlBoolean(PerformCompareByte(x.Value, y.Value) == EComparison.GT);
}
/// <devdoc>
/// <para>
/// Compares the first <see cref='System.Data.SqlTypes.SqlBinary'/> for being less than or equal to the second <see cref='System.Data.SqlTypes.SqlBinary'/>.
/// </para>
/// </devdoc>
public static SqlBoolean operator<=(SqlBinary x, SqlBinary y) {
if (x.IsNull || y.IsNull)
return SqlBoolean.Null;
EComparison cmpResult = PerformCompareByte(x.Value, y.Value);
return new SqlBoolean(cmpResult == EComparison.LT || cmpResult == EComparison.EQ);
}
/// <devdoc>
/// <para>
/// Compares the first <see cref='System.Data.SqlTypes.SqlBinary'/> for being greater than or equal the second <see cref='System.Data.SqlTypes.SqlBinary'/>.
/// </para>
/// </devdoc>
public static SqlBoolean operator>=(SqlBinary x, SqlBinary y) {
if (x.IsNull || y.IsNull)
return SqlBoolean.Null;
EComparison cmpResult = PerformCompareByte(x.Value, y.Value);
return new SqlBoolean(cmpResult == EComparison.GT || cmpResult == EComparison.EQ);
}
//--------------------------------------------------
// Alternative methods for overloaded operators
//--------------------------------------------------
// Alternative method for operator +
public static SqlBinary Add(SqlBinary x, SqlBinary y) {
return x + y;
}
public static SqlBinary Concat(SqlBinary x, SqlBinary y) {
return x + y;
}
// Alternative method for operator ==
public static SqlBoolean Equals(SqlBinary x, SqlBinary y) {
return (x == y);
}
// Alternative method for operator !=
public static SqlBoolean NotEquals(SqlBinary x, SqlBinary y) {
return (x != y);
}
// Alternative method for operator <
public static SqlBoolean LessThan(SqlBinary x, SqlBinary y) {
return (x < y);
}
// Alternative method for operator >
public static SqlBoolean GreaterThan(SqlBinary x, SqlBinary y) {
return (x > y);
}
// Alternative method for operator <=
public static SqlBoolean LessThanOrEqual(SqlBinary x, SqlBinary y) {
return (x <= y);
}
// Alternative method for operator >=
public static SqlBoolean GreaterThanOrEqual(SqlBinary x, SqlBinary y) {
return (x >= y);
}
// Alternative method for conversions.
public SqlGuid ToSqlGuid() {
return (SqlGuid)this;
}
// IComparable
// Compares this object to another object, returning an integer that
// indicates the relationship.
// Returns a value less than zero if this < object, zero if this = object,
// or a value greater than zero if this > object.
// null is considered to be less than any instance.
// If object is not of same type, this method throws an ArgumentException.
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public int CompareTo(Object value) {
if (value is SqlBinary) {
SqlBinary i = (SqlBinary)value;
return CompareTo(i);
}
throw ADP.WrongType(value.GetType(), typeof(SqlBinary));
}
public int CompareTo(SqlBinary value) {
// If both Null, consider them equal.
// Otherwise, Null is less than anything.
if (IsNull)
return value.IsNull ? 0 : -1;
else if (value.IsNull)
return 1;
if (this < value) return -1;
if (this > value) return 1;
return 0;
}
// Compares this instance with a specified object
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public override bool Equals(Object value) {
if (!(value is SqlBinary)) {
return false;
}
SqlBinary i = (SqlBinary)value;
if (i.IsNull || IsNull)
return (i.IsNull && IsNull);
else
return (this == i).Value;
}
// Hash a byte array.
// Trailing zeroes/spaces would affect the hash value, so caller needs to
// perform trimming as necessary.
internal static int HashByteArray(byte[] rgbValue, int length)
{
SQLDebug.Check(length >= 0);
if (length <= 0)
return 0;
SQLDebug.Check(rgbValue.Length >= length);
int ulValue = 0;
int ulHi;
// Size of CRC window (hashing bytes, ssstr, sswstr, numeric)
const int x_cbCrcWindow = 4;
// const int iShiftVal = (sizeof ulValue) * (8*sizeof(char)) - x_cbCrcWindow;
const int iShiftVal = 4 * 8 - x_cbCrcWindow;
for(int i = 0; i < length; i++)
{
ulHi = (ulValue >> iShiftVal) & 0xff;
ulValue <<= x_cbCrcWindow;
ulValue = ulValue ^ rgbValue[i] ^ ulHi;
}
return ulValue;
}
// For hashing purpose
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public override int GetHashCode()
{
if (IsNull)
return 0;
//First trim off extra '\0's
int cbLen = m_value.Length;
while (cbLen > 0 && m_value[cbLen - 1] == 0)
--cbLen;
return HashByteArray(m_value, cbLen);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
XmlSchema IXmlSerializable.GetSchema() { return null; }
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
void IXmlSerializable.ReadXml(XmlReader reader) {
string isNull = reader.GetAttribute("nil", XmlSchema.InstanceNamespace);
if (isNull != null && XmlConvert.ToBoolean(isNull)) {
// VSTFDevDiv# 479603 - SqlTypes read null value infinitely and never read the next value. Fix - Read the next value.
reader.ReadElementString();
m_value = null;
}
else {
string base64 = reader.ReadElementString();
if (base64 == null) {
m_value = new byte[0];
}
else {
base64 = base64.Trim();
if (base64.Length == 0) {
m_value = new byte[0];
}
else {
m_value = Convert.FromBase64String(base64);
}
}
}
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
void IXmlSerializable.WriteXml(XmlWriter writer) {
if (IsNull) {
writer.WriteAttributeString("xsi", "nil", XmlSchema.InstanceNamespace, "true");
}
else {
writer.WriteString(Convert.ToBase64String(m_value));
}
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static XmlQualifiedName GetXsdType(XmlSchemaSet schemaSet) {
return new XmlQualifiedName("base64Binary", XmlSchema.Namespace);
}
/// <devdoc>
/// <para>
/// Represents a null value that can be assigned to
/// the <see cref='System.Data.SqlTypes.SqlBinary.Value'/> property of an
/// instance of the <see cref='System.Data.SqlTypes.SqlBinary'/> class.
/// </para>
/// </devdoc>
public static readonly SqlBinary Null = new SqlBinary(true);
} // SqlBinary
} // namespace System.Data.SqlTypes
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