|
//------------------------------------------------------------------------------
// <copyright file="RegexGroup.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
// Group represents the substring or substrings that
// are captured by a single capturing group after one
// regular expression match.
namespace System.Text.RegularExpressions {
using System.Security.Permissions;
using System.Runtime.Serialization;
/// <devdoc>
/// Group
/// represents the results from a single capturing group. A capturing group can
/// capture zero, one, or more strings in a single match because of quantifiers, so
/// Group supplies a collection of Capture objects.
/// </devdoc>
#if !SILVERLIGHT
[ Serializable() ]
#endif
public class Group : Capture {
// the empty group object
internal static Group _emptygroup = new Group(String.Empty, new int[0], 0, string.Empty);
internal int[] _caps;
internal int _capcount;
internal CaptureCollection _capcoll;
#if !SILVERLIGHT
[OptionalField]
#endif
internal string _name;
internal Group(String text, int[] caps, int capcount, string name)
: base(text, capcount == 0 ? 0 : caps[(capcount - 1) * 2],
capcount == 0 ? 0 : caps[(capcount * 2) - 1]) {
_caps = caps;
_capcount = capcount;
_name = name;
}
/*
* True if the match was successful
*/
/// <devdoc>
/// <para>Indicates whether the match is successful.</para>
/// </devdoc>
public bool Success {
get {
return _capcount != 0;
}
}
/// <summary>
/// Provides the name of the group.
/// </summary>
public string Name
{
get
{
return _name;
}
}
/*
* The collection of all captures for this group
*/
/// <devdoc>
/// <para>
/// Returns a collection of all the captures matched by the capturing
/// group, in innermost-leftmost-first order (or innermost-rightmost-first order if
/// compiled with the "r" option). The collection may have zero or more items.
/// </para>
/// </devdoc>
public CaptureCollection Captures {
get {
if (_capcoll == null)
_capcoll = new CaptureCollection(this);
return _capcoll;
}
}
/*
* Convert to a thread-safe object by precomputing cache contents
*/
/// <devdoc>
/// <para>Returns
/// a Group object equivalent to the one supplied that is safe to share between
/// multiple threads.</para>
/// </devdoc>
#if !SILVERLIGHT
[HostProtection(Synchronization=true)]
static public Group Synchronized(Group inner) {
#else
static internal Group Synchronized(Group inner) {
#endif
if (inner == null)
throw new ArgumentNullException("inner");
// force Captures to be computed.
CaptureCollection capcoll;
Capture dummy;
capcoll = inner.Captures;
if (inner._capcount > 0)
dummy = capcoll[0];
return inner;
}
}
}
|