System.Data.DataTable.DSRowDiffIdUsageSection.Prepare C# (CSharp) Method

Prepare() private method

private Prepare ( DataSet ds ) : void
ds DataSet
return void
            internal void Prepare(DataSet ds)
            {
                Debug.Assert(_targetDS == null, "do not reuse this section");
                Debug.Assert(ds != null);

                _targetDS = ds;
#if DEBUG
                // initialize list of tables out of current tables
                // note: it might remain empty (still initialization is needed for assert to operate)
                if (RowDiffIdUsageSection.s_usedTables == null)
                    RowDiffIdUsageSection.s_usedTables = new List<DataTable>();
#endif 
                for (int tableIndex = 0; tableIndex < ds.Tables.Count; ++tableIndex)
                {
                    DataTable table = ds.Tables[tableIndex];
#if DEBUG
                    Debug.Assert(!RowDiffIdUsageSection.s_usedTables.Contains(table), "Nested call with same table can cause data corruption!");
                    RowDiffIdUsageSection.s_usedTables.Add(table);
#endif
                    Debug.Assert(table._rowDiffId == null, "rowDiffId wasn't previously cleared");
                    table._rowDiffId = null;
                }
            }

Usage Example

        internal XmlReadMode ReadXml(XmlReader reader, XmlReadMode mode, bool denyResolving)
        {
            IntPtr hscp;
            Bid.ScopeEnter(out hscp, "<ds.DataSet.ReadXml|INFO> %d#, mode=%d{ds.XmlReadMode}, denyResolving=%d{bool}\n", ObjectID, (int)mode, denyResolving);
            try {

                XmlReadMode ret = mode;

                if (reader == null)
                    return ret;

                if (mode == XmlReadMode.Auto) {
                    // Dev11 915079: nested ReadXml calls on the same DataSet must be done outside of RowDiffIdUsage scope
                    return ReadXml(reader);
                }

                DataTable.DSRowDiffIdUsageSection rowDiffIdUsage = new DataTable.DSRowDiffIdUsageSection();
                try {

                    bool fSchemaFound = false;
                    bool fDataFound = false;
                    bool fIsXdr = false;
                    int iCurrentDepth = -1;

                    // Dev11 904428: prepare and cleanup rowDiffId hashtable
                    rowDiffIdUsage.Prepare(this);

                    if (reader is XmlTextReader)
                        ((XmlTextReader)reader).WhitespaceHandling = WhitespaceHandling.Significant;

                    XmlDocument xdoc = new XmlDocument(); // we may need this to infer the schema

                    if ((mode != XmlReadMode.Fragment) && (reader.NodeType == XmlNodeType.Element))
                        iCurrentDepth = reader.Depth;

                    reader.MoveToContent();
                    XmlDataLoader xmlload = null;

                    if (reader.NodeType == XmlNodeType.Element) {
                        XmlElement topNode = null;
                        if (mode == XmlReadMode.Fragment) {
                            xdoc.AppendChild(xdoc.CreateElement("ds_sqlXmlWraPPeR"));
                            topNode = xdoc.DocumentElement;
                        }
                        else { //handle the top node
                            if ((reader.LocalName == Keywords.DIFFGRAM) && (reader.NamespaceURI == Keywords.DFFNS)) {
                                if ((mode == XmlReadMode.DiffGram) || (mode == XmlReadMode.IgnoreSchema)) {
                                    this.ReadXmlDiffgram(reader);
                                    // read the closing tag of the current element
                                    ReadEndElement(reader);
                                }
                                else {
                                    reader.Skip();
                                }
                                return ret;
                            }

                            if (reader.LocalName == Keywords.XDR_SCHEMA && reader.NamespaceURI == Keywords.XDRNS) {
                                // load XDR schema and exit
                                if ((mode != XmlReadMode.IgnoreSchema) && (mode != XmlReadMode.InferSchema) &&
                                    (mode != XmlReadMode.InferTypedSchema))
                                {
                                    ReadXDRSchema(reader);
                                }
                                else {
                                    reader.Skip();
                                }
                                return ret; //since the top level element is a schema return
                            }

                            if (reader.LocalName == Keywords.XSD_SCHEMA && reader.NamespaceURI == Keywords.XSDNS) {
                                // load XSD schema and exit
                                if ((mode != XmlReadMode.IgnoreSchema) && (mode != XmlReadMode.InferSchema) &&
                                    (mode != XmlReadMode.InferTypedSchema))
                                {
                                    ReadXSDSchema(reader, denyResolving);
                                }
                                else
                                    reader.Skip();
                                return ret; //since the top level element is a schema return
                            }

                            if (reader.LocalName == Keywords.XSD_SCHEMA && reader.NamespaceURI.StartsWith(Keywords.XSD_NS_START, StringComparison.Ordinal))
                                throw ExceptionBuilder.DataSetUnsupportedSchema(Keywords.XSDNS);

                            // now either the top level node is a table and we load it through dataReader...
                            // ... or backup the top node and all its attributes
                            topNode = xdoc.CreateElement(reader.Prefix, reader.LocalName, reader.NamespaceURI);
                            if (reader.HasAttributes) {
                                int attrCount = reader.AttributeCount;
                                for (int i = 0; i < attrCount; i++) {
                                    reader.MoveToAttribute(i);
                                    if (reader.NamespaceURI.Equals(Keywords.XSD_XMLNS_NS))
                                        topNode.SetAttribute(reader.Name, reader.GetAttribute(i));
                                    else {
                                        XmlAttribute attr = topNode.SetAttributeNode(reader.LocalName, reader.NamespaceURI);
                                        attr.Prefix = reader.Prefix;
                                        attr.Value = reader.GetAttribute(i);
                                    }
                                }
                            }
                            reader.Read();
                        }

                        while (MoveToElement(reader, iCurrentDepth)) {

                            if (reader.LocalName == Keywords.XDR_SCHEMA && reader.NamespaceURI == Keywords.XDRNS) {
                                // load XDR schema
                                if (!fSchemaFound && !fDataFound && (mode != XmlReadMode.IgnoreSchema) && (mode != XmlReadMode.InferSchema) &&
                                    (mode != XmlReadMode.InferTypedSchema))
                                {
                                    ReadXDRSchema(reader);
                                    fSchemaFound = true;
                                    fIsXdr = true;
                                }
                                else {
                                    reader.Skip();
                                }
                                continue;
                            }

                            if (reader.LocalName == Keywords.XSD_SCHEMA && reader.NamespaceURI == Keywords.XSDNS) {
                                // load XSD schema and exit
                                if ((mode != XmlReadMode.IgnoreSchema) && (mode != XmlReadMode.InferSchema) &&
                                    (mode != XmlReadMode.InferTypedSchema))
                                {
                                    ReadXSDSchema(reader, denyResolving);
                                    fSchemaFound = true;
                                }
                                else {
                                    reader.Skip();
                                }
                                continue;
                            }

                            if ((reader.LocalName == Keywords.DIFFGRAM) && (reader.NamespaceURI == Keywords.DFFNS)) {
                                if ((mode == XmlReadMode.DiffGram) || (mode == XmlReadMode.IgnoreSchema)) {
                                    this.ReadXmlDiffgram(reader);
                                    ret = XmlReadMode.DiffGram;
                                }
                                else {
                                    reader.Skip();
                                }
                                continue;
                            }

                            if (reader.LocalName == Keywords.XSD_SCHEMA && reader.NamespaceURI.StartsWith(Keywords.XSD_NS_START, StringComparison.Ordinal))
                                throw ExceptionBuilder.DataSetUnsupportedSchema(Keywords.XSDNS);

                            if (mode == XmlReadMode.DiffGram) {
                                reader.Skip();
                                continue; // we do not read data in diffgram mode
                            }

                            // if we are here we found some data
                            fDataFound = true;

                            if (mode == XmlReadMode.InferSchema || mode == XmlReadMode.InferTypedSchema) { //save the node in DOM until the end;
                                XmlNode node = xdoc.ReadNode(reader);
                                topNode.AppendChild(node);
                            }
                            else {
                                if (xmlload == null)
                                    xmlload = new XmlDataLoader(this, fIsXdr, topNode, mode == XmlReadMode.IgnoreSchema);
                                xmlload.LoadData(reader);
                            }
                        } //end of the while

                        // read the closing tag of the current element
                        ReadEndElement(reader);

                        // now top node contains the data part
                        xdoc.AppendChild(topNode);
                        if (xmlload == null)
                            xmlload = new XmlDataLoader(this, fIsXdr, mode == XmlReadMode.IgnoreSchema);

                        if (mode == XmlReadMode.DiffGram) {
                            // we already got the diffs through XmlReader interface
                            return ret;
                        }

                        // Load Data
                        if (mode == XmlReadMode.InferSchema || mode == XmlReadMode.InferTypedSchema) {
                            InferSchema(xdoc, null, mode);
                            ret = XmlReadMode.InferSchema;
                            xmlload.FromInference = true;
                            //                }
                            try {
                                xmlload.LoadData(xdoc);
                            }
                            finally {
                                xmlload.FromInference = false;
                            }
                        }
                    }

                    return ret;
                }
                finally {
                    // Dev11 904428: prepare and cleanup rowDiffId hashtable
                    rowDiffIdUsage.Cleanup();
                }
            }
            finally {
                Bid.ScopeLeave(ref hscp);
            }
        }
All Usage Examples Of System.Data.DataTable.DSRowDiffIdUsageSection::Prepare
DataTable.DSRowDiffIdUsageSection