SQLGuid.cs source code in C# .NET

                        Code:
                         / FX-1434 / FX-1434 / 1.0 / untmp / whidbey / REDBITS / ndp / fx / src / Data / System / Data / SQLTypes / SQLGuid.cs / 1 / SQLGuid.cs
                        
                        
                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
//  
// junfang 
// [....]
// [....] 
//----------------------------------------------------------------------------- 

//************************************************************************* 
// @File: SqlGuid.cs
//
// Create by:    JunFang
// 
// Purpose: Implementation of SqlGuid which is equivalent to
//            data type "uniqueidentifier" in SQL Server 
// 
// Notes:
// 
// History:
//
//   11/1/99  JunFang    Created.
// 
// @EndHeader@
//************************************************************************* 
 
using System;
using System.Data.Common; 
using System.Xml;
using System.Xml.Schema;
using System.Xml.Serialization;
 
namespace System.Data.SqlTypes {
 
    ///  
    ///    
    ///       Represents a globally unique identifier to be stored in 
    ///       or retrieved from a database.
    ///    
    /// 
    [Serializable] 
    [XmlSchemaProvider("GetXsdType")]
    public struct SqlGuid : INullable, IComparable, IXmlSerializable { 
        private static readonly int SizeOfGuid = 16; 

        // Comparison orders. 
        private static readonly int[] x_rgiGuidOrder = new int[16]
        {10, 11, 12, 13, 14, 15, 8, 9, 6, 7, 4, 5, 0, 1, 2, 3};

        private byte[] m_value; // the SqlGuid is null if m_value is null 

        // constructor 
        // construct a SqlGuid.Null 
        private SqlGuid(bool fNull) {
            m_value = null; 
        }

        /// 
        ///    [To be supplied.] 
        /// 
        public SqlGuid(byte[] value) { 
            if (value == null || value.Length != SizeOfGuid) 
                throw new ArgumentException(SQLResource.InvalidArraySizeMessage);
 
            m_value = new byte[SizeOfGuid];
            value.CopyTo(m_value, 0);
        }
 
        /// 
        ///    [To be supplied.] 
        ///  
        internal SqlGuid(byte[] value, bool ignored) {
            if (value == null || value.Length != SizeOfGuid) 
                throw new ArgumentException(SQLResource.InvalidArraySizeMessage);

            m_value = value;
        } 

        ///  
        ///    [To be supplied.] 
        /// 
        public SqlGuid(String s) { 
            m_value = (new Guid(s)).ToByteArray();
        }

        ///  
        ///    [To be supplied.]
        ///  
        public SqlGuid(Guid g) { 
            m_value = g.ToByteArray();
        } 

        public SqlGuid(int a, short b, short c, byte d, byte e, byte f, byte g, byte h, byte i, byte j, byte k)
            : this(new Guid(a, b, c, d, e, f, g, h, i, j, k))
        { 
        }
 
 
        // INullable
        ///  
        ///    [To be supplied.]
        /// 
        public bool IsNull {
            get { return(m_value == null);} 
        }
 
        // property: Value 
        /// 
        ///    [To be supplied.] 
        /// 
        public Guid Value {
            get {
                if (IsNull) 
                    throw new SqlNullValueException();
                else 
                    return new Guid(m_value); 
            }
        } 

        // Implicit conversion from Guid to SqlGuid
        /// 
        ///    [To be supplied.] 
        /// 
        public static implicit operator SqlGuid(Guid x) { 
            return new SqlGuid(x); 
        }
 
        // Explicit conversion from SqlGuid to Guid. Throw exception if x is Null.
        /// 
        ///    [To be supplied.]
        ///  
        public static explicit operator Guid(SqlGuid x) {
            return x.Value; 
        } 

        ///  
        ///    [To be supplied.]
        /// 
        public byte[] ToByteArray() {
            byte[] ret = new byte[SizeOfGuid]; 
            m_value.CopyTo(ret, 0);
            return ret; 
        } 

        ///  
        ///    [To be supplied.]
        /// 
        public override String ToString() {
            if (IsNull) 
                return SQLResource.NullString;
 
            Guid g = new Guid(m_value); 
            return g.ToString();
        } 

        /// 
        ///    [To be supplied.]
        ///  
        public static SqlGuid Parse(String s) {
            if (s == SQLResource.NullString) 
                return SqlGuid.Null; 
            else
                return new SqlGuid(s); 
        }


        // Comparison operators 
        private static EComparison Compare(SqlGuid x, SqlGuid y) {
            //Swap to the correct order to be compared 
            for (int i = 0; i < SizeOfGuid; i++) { 
                byte    b1, b2;
 
                b1 = x.m_value [x_rgiGuidOrder[i]];
                b2 = y.m_value [x_rgiGuidOrder[i]];
                if (b1 != b2)
                    return(b1 < b2) ? EComparison.LT : EComparison.GT; 
            }
            return EComparison.EQ; 
        } 

 

        // Implicit conversions

        // Explicit conversions 

        // Explicit conversion from SqlString to SqlGuid 
        ///  
        ///    [To be supplied.]
        ///  
        public static explicit operator SqlGuid(SqlString x) {
            return x.IsNull ? Null : new SqlGuid(x.Value);
        }
 
        // Explicit conversion from SqlBinary to SqlGuid
        ///  
        ///    [To be supplied.] 
        /// 
        public static explicit operator SqlGuid(SqlBinary x) { 
            return x.IsNull ? Null : new SqlGuid(x.Value);
        }

        // Overloading comparison operators 
        /// 
        ///    [To be supplied.] 
        ///  
        public static SqlBoolean operator==(SqlGuid x, SqlGuid y) {
            return(x.IsNull || y.IsNull) ? SqlBoolean.Null : new SqlBoolean(Compare(x, y) == EComparison.EQ); 
        }

        /// 
        ///    [To be supplied.] 
        /// 
        public static SqlBoolean operator!=(SqlGuid x, SqlGuid y) { 
            return ! (x == y); 
        }
 
        /// 
        ///    [To be supplied.]
        /// 
        public static SqlBoolean operator<(SqlGuid x, SqlGuid y) { 
            return(x.IsNull || y.IsNull) ? SqlBoolean.Null : new SqlBoolean(Compare(x, y) == EComparison.LT);
        } 
 
        /// 
        ///    [To be supplied.] 
        /// 
        public static SqlBoolean operator>(SqlGuid x, SqlGuid y) {
            return(x.IsNull || y.IsNull) ? SqlBoolean.Null : new SqlBoolean(Compare(x, y) == EComparison.GT);
        } 

        ///  
        ///    [To be supplied.] 
        /// 
        public static SqlBoolean operator<=(SqlGuid x, SqlGuid y) { 
            if (x.IsNull || y.IsNull)
                return SqlBoolean.Null;

            EComparison cmp = Compare(x, y); 
            return new SqlBoolean(cmp == EComparison.LT || cmp == EComparison.EQ);
        } 
 
        /// 
        ///    [To be supplied.] 
        /// 
        public static SqlBoolean operator>=(SqlGuid x, SqlGuid y) {
            if (x.IsNull || y.IsNull)
                return SqlBoolean.Null; 

            EComparison cmp = Compare(x, y); 
            return new SqlBoolean(cmp == EComparison.GT || cmp == EComparison.EQ); 
        }
 
        //--------------------------------------------------
        // Alternative methods for overloaded operators
        //--------------------------------------------------
 
        // Alternative method for operator ==
        public static SqlBoolean Equals(SqlGuid x, SqlGuid y) { 
            return (x == y); 
        }
 
        // Alternative method for operator !=
        public static SqlBoolean NotEquals(SqlGuid x, SqlGuid y) {
            return (x != y);
        } 

        // Alternative method for operator < 
        public static SqlBoolean LessThan(SqlGuid x, SqlGuid y) { 
            return (x < y);
        } 

        // Alternative method for operator >
        public static SqlBoolean GreaterThan(SqlGuid x, SqlGuid y) {
            return (x > y); 
        }
 
        // Alternative method for operator <= 
        public static SqlBoolean LessThanOrEqual(SqlGuid x, SqlGuid y) {
            return (x <= y); 
        }

        // Alternative method for operator >=
        public static SqlBoolean GreaterThanOrEqual(SqlGuid x, SqlGuid y) { 
            return (x >= y);
        } 
 
        // Alternative method for conversions.
 
        public SqlString ToSqlString() {
            return (SqlString)this;
        }
 
        public SqlBinary ToSqlBinary() {
            return (SqlBinary)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. 
        /// 
        ///    [To be supplied.] 
        /// 
        public int CompareTo(Object value) {
            if (value is SqlGuid) {
                SqlGuid i = (SqlGuid)value; 

                return CompareTo(i); 
            } 
            throw ADP.WrongType(value.GetType(), typeof(SqlGuid));
        } 

        public int CompareTo(SqlGuid 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 
        ///  
        ///    [To be supplied.]
        ///  
        public override bool Equals(Object value) {
            if (!(value is SqlGuid)) {
                return false;
            } 

            SqlGuid i = (SqlGuid)value; 
 
            if (i.IsNull || IsNull)
                return (i.IsNull && IsNull); 
            else
                return (this == i).Value;
        }
 
        // For hashing purpose
        ///  
        ///    [To be supplied.] 
        /// 
        public override int GetHashCode() { 
            return IsNull ? 0 : Value.GetHashCode();
        }

        ///  
        ///    [To be supplied.]
        ///  
        XmlSchema IXmlSerializable.GetSchema() { return null; } 

        ///  
        ///    [To be supplied.]
        /// 
        void IXmlSerializable.ReadXml(XmlReader reader) {
            string isNull = reader.GetAttribute("nil", XmlSchema.InstanceNamespace); 
            if (isNull != null && XmlConvert.ToBoolean(isNull)) {
                m_value = null; 
            } 
            else {
                m_value = new Guid(reader.ReadElementString()).ToByteArray(); 
            }
        }

        ///  
        ///    [To be supplied.]
        ///  
        void IXmlSerializable.WriteXml(XmlWriter writer) { 
            if (IsNull) {
                writer.WriteAttributeString("xsi", "nil", XmlSchema.InstanceNamespace, "true"); 
            }
            else {
                writer.WriteString(XmlConvert.ToString(new Guid(m_value)));
            } 
        }
 
        ///  
        ///    [To be supplied.]
        ///  
        public static XmlQualifiedName GetXsdType(XmlSchemaSet schemaSet) {
            return new XmlQualifiedName("string", XmlSchema.Namespace);
        }
 
        /// 
        ///    [To be supplied.] 
        ///  
        public static readonly SqlGuid Null     = new SqlGuid(true);
 
    } // SqlGuid

} // namespace System.Data.SqlTypes
 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
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SQLGuid.cs source code in C# .NET

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