OutputScopeManager.cs source code in C# .NET

                        Code:
                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / XmlUtils / System / Xml / Xsl / Xslt / OutputScopeManager.cs / 1305376 / OutputScopeManager.cs
                        
                        
                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// [....] 
//-----------------------------------------------------------------------------
using System; 
using System.Diagnostics; 
using System.Xml;
using System.Collections; 

namespace System.Xml.Xsl.Xslt {
    internal class OutputScopeManager {
        public struct ScopeReord { 
            public int        scopeCount;
            public string     prefix; 
            public string     nsUri; 
        }
        ScopeReord[] records = new ScopeReord[32]; 
        int lastRecord = 0;
        int lastScopes = 0;  // This is cash of records[lastRecord].scopeCount field;
                             // most often we will have PushScope()/PopScope pare over the same record.
                             // It has sence to avoid adresing this field through array access. 

        public OutputScopeManager() { 
            Reset(); 
        }
 
        public void Reset() {
//          AddNamespace(null, null);                  --  lookup barier
            records[0].prefix = null;
            records[0].nsUri  = null; 
            PushScope();
        } 
 
        public void PushScope() {
            lastScopes ++; 
        }

        public void PopScope() {
            if (0 < lastScopes) { 
                lastScopes --;
            } 
            else { 
                while(records[-- lastRecord].scopeCount == 0) ;
                lastScopes = records[lastRecord].scopeCount; 
                lastScopes --;
            }
        }
 
        // This can be ns declaration or ns exclussion. Las one when prefix == null;
        public void AddNamespace(string prefix, string uri) { 
            Debug.Assert(prefix != null); 
            Debug.Assert(uri    != null);
//            uri = nameTable.Add(uri); 
            AddRecord(prefix, uri);
        }

        private void AddRecord(string prefix, string uri) { 
            records[lastRecord].scopeCount = lastScopes;
            lastRecord ++; 
            if (lastRecord == records.Length) { 
                ScopeReord[] newRecords = new ScopeReord[lastRecord * 2];
                Array.Copy(records, 0, newRecords, 0, lastRecord); 
                records = newRecords;
            }
            lastScopes = 0;
            records[lastRecord].prefix = prefix; 
            records[lastRecord].nsUri  = uri;
        } 
 
        // There are some cases where we can't predict namespace content. To garantee correct results we should output all
        // literal namespaces once again. 
        //  all prefixes should be invalidated
        //  all prefixes should be invalidated
        //  prefixe "foo" should be invalidated
        //  prefixe "foo" should be invalidated 
        //  no invalidations reqired
        //  all prefixes should be invalidated but not default "" 
        //  all prefixes should be invalidated but not default "" 
        //  We can try to invalidate only foo prefix, but there to many thinks to consider here.
        //                                            So for now if attribute has non-null namespace it invalidates all prefixes in the 
        //                                            scope of its element.
        //
        //  all prefixes are invalidated for the current element scope
        //  no invalidations needed 
        //  if the node is either attribute or namespace, all prefixes are invalidated for the current element scope
        //            if the node is element, new scope is created, and all prefixes are invalidated 
        //            otherwise, no invalidations needed 

        //// We need following methods: 
        //public void InvalidatePrefix(string prefix) {
        //    Debug.Assert(prefix != null);
        //    if (LookupNamespace(prefix) == null) { // This is optimisation. May be better just add this record?
        //        return; 
        //    }
        //    AddRecord(prefix, null); 
        //} 

        public void InvalidateAllPrefixes() { 
            if (records[lastRecord].prefix == null) {
                return;                            // Averything was invalidated already. Nothing to do.
            }
            AddRecord(null, null); 
        }
 
        public void InvalidateNonDefaultPrefixes() { 
            string defaultNs = LookupNamespace(string.Empty);
            if (defaultNs == null) {             // We don't know default NS anyway. 
                InvalidateAllPrefixes();
            }
            else {
                if ( 
                    records[lastRecord    ].prefix.Length == 0 &&
                    records[lastRecord - 1].prefix == null 
                ) { 
                    return;                       // Averything was already done
                } 
                AddRecord(null, null);
                AddRecord(string.Empty, defaultNs);
            }
        } 

        public string LookupNamespace(string prefix) { 
            Debug.Assert(prefix != null); 
            for (
                int record = lastRecord;              // from last record 
                 records[record].prefix != null;      // till lookup barrier
                -- record                             // in reverce direction
            ) {
                Debug.Assert(0 < record, "first record is lookup bariaer, so we don't need to check this condition runtime"); 
                if (records[record].prefix == prefix) {
                    return records[record].nsUri; 
                } 
            }
            return null; 
        }
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
Link Menu

Network programming in C#, Network Programming in VB.NET, Network Programming in .NET
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
OutputScopeManager.cs source code in C# .NET

Source code for the .NET framework in C#

Code:

Link Menu
