File size: 2,946 Bytes
8c763fb | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 | // Copyright (c) Microsoft Corporation.
// Licensed under the MIT License.
using System.Collections;
using Dbg = System.Management.Automation.Diagnostics;
namespace System.Management.Automation.Remoting
{
/// <summary>
/// Provides an enumerator for iterating through a multi-dimensional array.
/// This is needed to encode multi-dimensional arrays in remote host methods.
/// </summary>
internal class Indexer : IEnumerable, IEnumerator
{
/// <summary>
/// Current.
/// </summary>
private readonly int[] _current;
/// <summary>
/// Lengths.
/// </summary>
private readonly int[] _lengths;
/// <summary>
/// Current.
/// </summary>
public object Current
{
get
{
return _current;
}
}
/// <summary>
/// Constructor for Indexer.
/// </summary>
internal Indexer(int[] lengths)
{
Dbg.Assert(lengths != null, "Expected lengths != null");
_lengths = lengths;
Dbg.Assert(CheckLengthsNonNegative(lengths), "Expected CheckLengthsNonNegative(lengths)");
_current = new int[lengths.Length];
}
/// <summary>
/// Check lengths non negative.
/// </summary>
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode")]
private static bool CheckLengthsNonNegative(int[] lengths)
{
for (int i = 0; i < lengths.Length; ++i)
{
if (lengths[i] < 0)
{
return false;
}
}
return true;
}
/// <summary>
/// Get enumerator.
/// </summary>
public IEnumerator GetEnumerator()
{
this.Reset();
return this;
}
/// <summary>
/// Reset.
/// </summary>
public void Reset()
{
for (int i = 0; i < _current.Length; ++i)
{
_current[i] = 0;
}
// Set last value to -1 so that MoveNext makes this 0,0,...,0.
if (_current.Length > 0)
{
_current[_current.Length - 1] = -1;
}
}
/// <summary>
/// Move next.
/// </summary>
public bool MoveNext()
{
for (int i = _lengths.Length - 1; i >= 0; --i)
{
// See if we can increment this dimension.
if (_current[i] < _lengths[i] - 1)
{
_current[i]++;
return true;
}
// Otherwise reset i and try to increment the next one.
_current[i] = 0;
}
return false;
}
}
}
|