/// <summary>Re-initializes internal state to be ready for re-use.</summary>
public void Reset()
{
// some declarations may be pending in nextScope
nextScope.ClearMappings();
// store active scopes for re-use
NamespaceScope scope = topScope;
if (scope != null)
{
// need to reset active scopes before storing them for re-use
scope.ClearMappings();
while (scope.parent != null)
{
scope = scope.parent;
scope.ClearMappings();
}
// attach free scopes to end of active scopes
scope.parent = nextScope;
// move the whole stack from topScope to nextScope
nextScope = topScope;
topScope = null;
}
// the 'xml' prefix is always declared
nextScope.AddMapping("xml", Constants.XmlUri);
}
/// <summary>Given a prefix mapping for a specific URI, this returns
/// the prefix mapping previously in effect for the same URI.</summary>
/// <remarks>This can be used to iterate backwards through the stack of
/// prefix mappings for a given URI.</remarks>
/// <param name="prefix"><see cref="ActiveMapping"/> instance for which
/// we want to find the instance previously in effect with the same URI.</param>
/// <returns><see cref="ActiveMapping"/> instance to look for,
/// or <c>null</c> if none exists.</returns>
public ActiveMapping PreviousUriMapping(ActiveMapping prefix)
{
string uri = prefix.Uri;
// check active mapping record
NamespaceMapping nsMapping = prefix.mappingsTop;
if (nsMapping == null || !nsMapping.declared)
{
string msg = Resources.GetString(RsId.UndeclaredMapping);
throw new XmlNamespacesException(String.Format(msg, prefix.Prefix));
}
// find a parent scope where the same URI maps to an "active" prefix
NamespaceScope scope = nsMapping.scope.parent;
while (scope != null)
{
nsMapping = scope.FindByUri(uri);
if (nsMapping != null)
{
ActiveMapping result = nsMapping.prefix;
// result must be different from prefix, since the same prefix
// cannot be "declared" with two different URIs at the same time
if (result.IsDeclared)
{
Debug.Assert(result != prefix, Resources.GetString(RsId.InternalNsError));
return(result);
}
}
scope = scope.parent;
}
return(null);
}
/// <summary>Returns the most recently added namespace mapping "in effect"
/// for a given URI.</summary>
/// <remarks>"In effect" means that the prefix mapping must <b>not</b> have
/// been "undeclared".</remarks>
/// <param name="uri">Namespace URI to get mapping for.</param>
/// <returns><see cref="ActiveMapping"/> instance for <c>uri</c>, or <c>null</c>
/// if there is no such mapping.</returns>
public ActiveMapping GetUriMapping(string uri)
{
NamespaceScope scope = topScope;
while (scope != null)
{
NamespaceMapping nsMapping = scope.FindByUri(uri);
if (nsMapping != null && nsMapping.declared)
{
return(nsMapping.prefix);
}
scope = scope.parent;
}
return(null);
}
/// <param name="prefixStr">String containing prefix sub-string.</param>
/// <param name="start">Start index of prefix sub-string.</param>
/// <param name="len">Length of prefix sub-string.</param>
public ActiveMapping GetPrefixMapping(string prefixStr, int start, int len)
{
NamespaceScope scope = topScope;
while (scope != null)
{
NamespaceMapping nsMapping = scope.FindByPrefix(prefixStr, start, len);
if (nsMapping != null)
{
return(nsMapping.prefix);
}
scope = scope.parent;
}
return(null);
}
/// <summary>Establishes a new mapping for the prefix associated with this
/// instance, to an URI in a namespace scope, and pushes it on the stack.</summary>
/// <param name="scope">Namespace scope the new mapping will be part of.</param>
/// <param name="uri">URI to be mapped to this instance's prefix.</param>
/// <returns>Newly added <see cref="NamespaceMapping"/>.</returns>
protected internal NamespaceMapping PushMapping(string uri, NamespaceScope scope)
{
NamespaceMapping result = namespaces.NewNSMapping();
result.prefix = this;
result.scope = scope;
result.declared = uri != null;
if (result.declared)
{
result.uri = uri;
}
else
{
result.uri = this.Uri;
}
result.next = mappingsTop;
mappingsTop = result;
return(result);
}
/// <summary>Deactivates namespace scope.</summary>
/// <remarks>All namespace mappings that became active with this scope
/// are going out of effect.</remarks>
public void PopScope()
{
if (nextScope.emptyLevels > 0)
{
nextScope.emptyLevels--;
}
else if (topScope == null) // don't pop too many times
{
string msg = Resources.GetString(RsId.NoActiveNsScope);
throw new InvalidOperationException(msg);
}
else
{
NamespaceScope oldNextScope = nextScope;
// clear pending declarations
oldNextScope.ClearMappings();
nextScope = topScope;
topScope = topScope.parent;
nextScope.parent = oldNextScope;
nextScope.ClearMappings();
}
}
/// <summary>Activates new namespace scope.</summary>
/// <remarks>All namespace mappings that were added since the last
/// call to <see cref="PushScope"/>are going into effect.</remarks>
public void PushScope()
{
if (nextScope.nsMappings.Count == 0)
{
nextScope.emptyLevels++;
}
else
{
NamespaceScope newNextScope = nextScope.parent;
nextScope.parent = topScope;
topScope = nextScope; // assume it was reset
if (newNextScope == null)
{
newNextScope = new NamespaceScope(this);
}
else
{
newNextScope.emptyLevels = 0;
}
nextScope = newNextScope;
}
}
/// <summary>Indicates if a namespace scope is the most recent scope.</summary>
/// <param name="scope"><see cref="NamespaceScope"/> to be checked.</param>
/// <returns><c>true</c> if <c>scope</c> is most recent, <c>false</c> otherwise.</returns>
protected internal bool IsLastScope(NamespaceScope scope)
{
return scope == topScope || scope == nextScope;
}
/// <summary>Re-initializes internal state to be ready for re-use.</summary>
public void Reset()
{
// some declarations may be pending in nextScope
nextScope.ClearMappings();
// store active scopes for re-use
NamespaceScope scope = topScope;
if (scope != null) {
// need to reset active scopes before storing them for re-use
scope.ClearMappings();
while (scope.parent != null) {
scope = scope.parent;
scope.ClearMappings();
}
// attach free scopes to end of active scopes
scope.parent = nextScope;
// move the whole stack from topScope to nextScope
nextScope = topScope;
topScope = null;
}
// the 'xml' prefix is always declared
nextScope.AddMapping("xml", Constants.XmlUri);
}
/// <summary>Activates new namespace scope.</summary>
/// <remarks>All namespace mappings that were added since the last
/// call to <see cref="PushScope"/>are going into effect.</remarks>
public void PushScope()
{
if (nextScope.nsMappings.Count == 0) {
nextScope.emptyLevels++;
}
else {
NamespaceScope newNextScope = nextScope.parent;
nextScope.parent = topScope;
topScope = nextScope; // assume it was reset
if (newNextScope == null)
newNextScope = new NamespaceScope(this);
else
newNextScope.emptyLevels = 0;
nextScope = newNextScope;
}
}
/// <summary>Deactivates namespace scope.</summary>
/// <remarks>All namespace mappings that became active with this scope
/// are going out of effect.</remarks>
public void PopScope()
{
if (nextScope.emptyLevels > 0)
nextScope.emptyLevels--;
else if (topScope == null) { // don't pop too many times
string msg = Resources.GetString(RsId.NoActiveNsScope);
throw new InvalidOperationException(msg);
}
else {
NamespaceScope oldNextScope = nextScope;
// clear pending declarations
oldNextScope.ClearMappings();
nextScope = topScope;
topScope = topScope.parent;
nextScope.parent = oldNextScope;
nextScope.ClearMappings();
}
}
/* Public Interface */
/// <summary>Initializes new instance.</summary>
public XmlNamespaces()
{
nextScope = new NamespaceScope(this);
// the 'xml' prefix is always declared
nextScope.AddMapping("xml", Constants.XmlUri);
}
/// <summary>Establishes a new mapping for the prefix associated with this
/// instance, to an URI in a namespace scope, and pushes it on the stack.</summary>
/// <param name="scope">Namespace scope the new mapping will be part of.</param>
/// <param name="uri">URI to be mapped to this instance's prefix.</param>
/// <returns>Newly added <see cref="NamespaceMapping"/>.</returns>
protected internal NamespaceMapping PushMapping(string uri, NamespaceScope scope)
{
NamespaceMapping result = namespaces.NewNSMapping();
result.prefix = this;
result.scope = scope;
result.declared = uri != null;
if (result.declared)
result.uri = uri;
else
result.uri = this.Uri;
result.next = mappingsTop;
mappingsTop = result;
return result;
}
/* Public Interface */
/// <summary>Initializes new instance.</summary>
public XmlNamespaces()
{
nextScope = new NamespaceScope(this);
// the 'xml' prefix is always declared
nextScope.AddMapping("xml", Constants.XmlUri);
}
/// <summary>Indicates if a namespace scope is the most recent scope.</summary>
/// <param name="scope"><see cref="NamespaceScope"/> to be checked.</param>
/// <returns><c>true</c> if <c>scope</c> is most recent, <c>false</c> otherwise.</returns>
protected internal bool IsLastScope(NamespaceScope scope)
{
return(scope == topScope || scope == nextScope);
}
