DataSet ReadXml ReadXmlSchema (from msdn)

代码

   
     

    
      
    
      private
    
       
    
      void
    
       DemonstrateReadWriteXMLDocumentWithStreamReader()
{
 
    
      //
    
       Create a DataSet with one table and two columns.
    
      

    
       DataSet OriginalDataSet 
    
      =
    
       
    
      new
    
       DataSet(
    
      "
    
      dataSet
    
      "
    
      );
 OriginalDataSet.Namespace
    
      =
    
       
    
      "
    
      NetFrameWork
    
      "
    
      ;
 DataTable table 
    
      =
    
       
    
      new
    
       DataTable(
    
      "
    
      table
    
      "
    
      );
 DataColumn idColumn 
    
      =
    
       
    
      new
    
       DataColumn(
    
      "
    
      id
    
      "
    
      , 
 Type.GetType(
    
      "
    
      System.Int32
    
      "
    
      ));
 idColumn.AutoIncrement
    
      =
    
       
    
      true
    
      ;

 DataColumn itemColumn 
    
      =
    
       
    
      new
    
       DataColumn(
    
      "
    
      item
    
      "
    
      );
 table.Columns.Add(idColumn);
 table.Columns.Add(itemColumn);
 OriginalDataSet.Tables.Add(table);

 
    
      //
    
       Add ten rows.
    
      

    
       DataRow newRow;
 
    
      for
    
      (
    
      int
    
       i 
    
      =
    
       
    
      0
    
      ; i 
    
      <
    
       
    
      10
    
      ; i
    
      ++
    
      )
 {
 newRow 
    
      =
    
       table.NewRow();
 newRow[
    
      "
    
      item
    
      "
    
      ]
    
      =
    
       
    
      "
    
      item 
    
      "
    
       
    
      +
    
       i;
 table.Rows.Add(newRow);
 }
 OriginalDataSet.AcceptChanges();

 
    
      //
    
       Print out values of each table in the DataSet 
 
    
      //
    
       using the function defined below.
    
      

    
       PrintValues(OriginalDataSet, 
    
      "
    
      Original DataSet
    
      "
    
      );

 
    
      //
    
       Write the schema and data to an XML file.
    
      

    
       
    
      string
    
       xmlFilename 
    
      =
    
       
    
      "
    
      XmlDocument.xml
    
      "
    
      ;

 
    
      //
    
       Use WriteXml to write the document.
    
      

    
       OriginalDataSet.WriteXml(xmlFilename);

 
    
      //
    
       Dispose of the original DataSet.
    
      

    
       OriginalDataSet.Dispose();

 
    
      //
    
       Create a new DataSet.
    
      

    
       DataSet newDataSet 
    
      =
    
       
    
      new
    
       DataSet(
    
      "
    
      New DataSet
    
      "
    
      );

 
    
      //
    
       Read the XML document into the DataSet.
    
      

    
       newDataSet.ReadXml(xmlFilename);

 
    
      //
    
       Print out values of each table in the DataSet 
 
    
      //
    
       using the function defined below.
    
      

    
       PrintValues(newDataSet,
    
      "
    
      New DataSet
    
      "
    
      );
}
 

    
      private
    
       
    
      void
    
       PrintValues(DataSet dataSet, 
    
      string
    
       label)
{
 Console.WriteLine(
    
      "
    
      \n
    
      "
    
       
    
      +
    
       label);
 
    
      foreach
    
      (DataTable table 
    
      in
    
       dataSet.Tables)
 {
 Console.WriteLine(
    
      "
    
      TableName: 
    
      "
    
       
    
      +
    
       table.TableName);
 
    
      foreach
    
      (DataRow row 
    
      in
    
       table.Rows)
 {
 
    
      foreach
    
      (DataColumn column 
    
      in
    
       table.Columns)
 {
 Console.Write(
    
      "
    
      \table 
    
      "
    
       
    
      +
    
       row[column] );
 }
 Console.WriteLine();
 }
 }
}
   
     

 

ReadXml 方法提供了只将数据或同时将数据和架构从 XML 文档读入 DataSet 的方式，而 ReadXmlSchema 方法仅读架构。若要同时读数据和架构，请使用包括 mode 参数的 ReadXML 重载之一，并将其值设置为 ReadSchema。

请注意，对于 WriteXml 和 WriteXmlSchema 方法也是如此。若要写入来自 DataSet 的 XML 数据或架构和数据两者，使用 WriteXml 方法。若要只写入架构，请使用 WriteXmlSchema 方法。