ExpressionNode.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / DotNET / DotNET / 8.0 / untmp / whidbey / REDBITS / ndp / fx / src / Data / System / Data / Filter / ExpressionNode.cs / 1 / ExpressionNode.cs
                        

                        
                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// [....] 
// [....]
// [....] 
//----------------------------------------------------------------------------- 

namespace System.Data { 
    using System;
    using System.Collections.Generic;
    using System.Data.Common;
    using System.Data.SqlTypes; 

    internal abstract class ExpressionNode { 
        private DataTable _table; 

        protected ExpressionNode(DataTable table) { 
            _table = table;
        }

        internal IFormatProvider FormatProvider { 
            get {
                return ((null != _table) ? _table.FormatProvider : System.Globalization.CultureInfo.CurrentCulture); 
            } 
        }
 
        internal virtual bool IsSqlColumn{
            get{
                return false;
            } 
        }
 
        protected DataTable table { 
            get { return _table; }
        } 

        protected void BindTable(DataTable table) {
            // when the expression is created, DataColumn may not be associated with a table yet
            _table = table; 
        }
 
        internal abstract void Bind(DataTable table, List list); 
        internal abstract object Eval();
        internal abstract object Eval(DataRow row, DataRowVersion version); 
        internal abstract object Eval(int[] recordNos);
        internal abstract bool IsConstant();
        internal abstract bool IsTableConstant();
        internal abstract bool HasLocalAggregate(); 
        internal abstract bool HasRemoteAggregate();
        internal abstract ExpressionNode Optimize(); 
        internal virtual bool DependsOn(DataColumn column) { 
            return false;
        } 

        internal static bool IsInteger(StorageType type) {
            return(type == StorageType.Int16 ||
                type == StorageType.Int32 || 
                type == StorageType.Int64 ||
                type == StorageType.UInt16 || 
                type == StorageType.UInt32 || 
                type == StorageType.UInt64 ||
                type == StorageType.SByte || 
                type == StorageType.Byte);
        }

        internal static bool IsIntegerSql(StorageType type) { 
            return(type == StorageType.Int16 ||
                type == StorageType.Int32 || 
                type == StorageType.Int64 || 
                type == StorageType.UInt16 ||
                type == StorageType.UInt32 || 
                type == StorageType.UInt64 ||
                type == StorageType.SByte  ||
                type == StorageType.Byte ||
                type == StorageType.SqlInt64 || 
                type == StorageType.SqlInt32 ||
                type == StorageType.SqlInt16 || 
                type == StorageType.SqlByte); 
        }
 
        internal static bool IsSigned(StorageType type) {
            return(type == StorageType.Int16 ||
                type == StorageType.Int32 ||
                type == StorageType.Int64 || 
                type == StorageType.SByte ||
                IsFloat(type)); 
        } 

        internal static bool IsSignedSql(StorageType type) { 
            return(type == StorageType.Int16 || // IsSigned(type)
                type == StorageType.Int32 ||
                type == StorageType.Int64 ||
                type == StorageType.SByte || 
                type == StorageType.SqlInt64 ||
                type == StorageType.SqlInt32 || 
                type == StorageType.SqlInt16 || 
                IsFloatSql(type));
        } 

        internal static bool IsUnsigned(StorageType type) {
            return(type == StorageType.UInt16 ||
                   type == StorageType.UInt32 || 
                   type == StorageType.UInt64 ||
                   type == StorageType.Byte); 
        } 

        internal static bool IsUnsignedSql(StorageType type) { 
            return(type == StorageType.UInt16 ||
                   type == StorageType.UInt32 ||
                   type == StorageType.UInt64 ||
                   type == StorageType.SqlByte ||// SqlByte represents an 8-bit unsigned integer, in the range of 0 through 255, 
                   type == StorageType.Byte);
        } 
 
        internal static bool IsNumeric(StorageType type) {
            return(IsFloat(type) || 
                   IsInteger(type));
        }

        internal static bool IsNumericSql(StorageType type) { 
            return(IsFloatSql(type) ||
                   IsIntegerSql(type)); 
        } 

        internal static bool IsFloat(StorageType type) { 
            return(type == StorageType.Single ||
                type == StorageType.Double ||
                type == StorageType.Decimal);
        } 

        internal static bool IsFloatSql(StorageType type) { 
            return(type == StorageType.Single || 
                type == StorageType.Double ||
                type == StorageType.Decimal || 
                type == StorageType.SqlDouble ||
                type == StorageType.SqlDecimal || // I expect decimal to be Integer!
                type == StorageType.SqlMoney ||   // if decimal is here, this should be definitely here!
                type == StorageType.SqlSingle); 
        }
 
    } 
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.

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