DataTable.ReadXml 方法

定義

命名空間:: System.Data

組件:: System.Data.dll

組件:: netstandard.dll

重要

部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。

將 XML 結構與資料讀取到 DataTable.

多載

名稱	Description
ReadXml(Stream)	利用指定的 StreamXML 結構與資料讀取。DataTable
ReadXml(TextReader)	利用指定的 TextReaderXML 結構與資料讀取。DataTable
ReadXml(String)	從指定的檔案讀取 XML 架構和資料。DataTable
ReadXml(XmlReader)	利用指定的 XmlReader. 將 XML 架構與資料讀取至DataTable

備註

此 ReadXml 方法提供一種僅讀取資料，或同時讀取資料與結構的資料 DataTable ，從 XML 文件中讀取的方法，而該 ReadXmlSchema 方法僅讀取結構。要同時讀取資料與結構，請使用包含參數的XmlReadMode超載，ReadXML並將其值設為 ReadSchema。

請注意，與WriteXmlSchema方法分別也是WriteXml同理。若要撰寫 XML 資料，或同時撰寫結構與資料 DataTable，請使用該 WriteXml 方法。如果只寫結構，就用這個 WriteXmlSchema 方法。

Note

InvalidOperationException若被讀取或寫IDynamicMetaObjectProvider入的欄位DataRow類型將被拋出，且未實作 IXmlSerializable。

ReadXml(Stream)

利用指定的 StreamXML 結構與資料讀取。DataTable

public:
 System::Data::XmlReadMode ReadXml(System::IO::Stream ^ stream);

public System.Data.XmlReadMode ReadXml(System.IO.Stream stream);

member this.ReadXml : System.IO.Stream -> System.Data.XmlReadMode

Public Function ReadXml (stream As Stream) As XmlReadMode

參數

stream: Stream

一個由 Stream衍生出來的物件。

傳回

XmlReadMode

他們 XmlReadMode 會讀取資料。

範例

以下範例會產生包含兩欄十列的。DataTable 範例是透過 DataTable 呼叫 WriteXml 該方法，將結構和資料寫入記憶體串流。範例中會建立第二個 DataTable ，並呼叫該 ReadXml 方法來填充結構與資料。

private static void DemonstrateReadWriteXMLDocumentWithStream()
{
    DataTable table = CreateTestTable("XmlDemo");
    PrintValues(table, "Original table");

    // Write the schema and data to XML in a memory stream.
    System.IO.MemoryStream xmlStream = new System.IO.MemoryStream();
    table.WriteXml(xmlStream, XmlWriteMode.WriteSchema);

    // Rewind the memory stream.
    xmlStream.Position = 0;

    DataTable newTable = new DataTable();
    newTable.ReadXml(xmlStream);

    // Print out values in the table.
    PrintValues(newTable, "New table");
}

private static DataTable CreateTestTable(string tableName)
{
    // Create a test DataTable with two columns and a few rows.
    DataTable table = new DataTable(tableName);
    DataColumn column = new DataColumn("id", typeof(System.Int32));
    column.AutoIncrement = true;
    table.Columns.Add(column);

    column = new DataColumn("item", typeof(System.String));
    table.Columns.Add(column);

    // Add ten rows.
    DataRow row;
    for (int i = 0; i <= 9; i++)
    {
        row = table.NewRow();
        row["item"] = "item " + i;
        table.Rows.Add(row);
    }

    table.AcceptChanges();
    return table;
}

private static void PrintValues(DataTable table, string label)
{
    // Display the contents of the supplied DataTable:
    Console.WriteLine(label);
    foreach (DataRow row in table.Rows)
    {
        foreach (DataColumn column in table.Columns)
        {
            Console.Write("\t{0}", row[column]);
        }
        Console.WriteLine();
    }
}

Private Sub DemonstrateReadWriteXMLDocumentWithStream()
  Dim table As DataTable = CreateTestTable("XmlDemo")
  PrintValues(table, "Original table")

  ' Write the schema and data to XML in a memory stream.
  Dim xmlStream As New System.IO.MemoryStream()
  table.WriteXml(xmlStream, XmlWriteMode.WriteSchema)

  ' Rewind the memory stream.
  xmlStream.Position = 0

  Dim newTable As New DataTable
  newTable.ReadXml(xmlStream)

  ' Print out values in the table.
  PrintValues(newTable, "New Table")
End Sub

Private Function CreateTestTable(ByVal tableName As String) As DataTable
  ' Create a test DataTable with two columns and a few rows.
  Dim table As New DataTable(tableName)
  Dim column As New DataColumn("id", GetType(System.Int32))
  column.AutoIncrement = True
  table.Columns.Add(column)

  column = New DataColumn("item", GetType(System.String))
  table.Columns.Add(column)

  ' Add ten rows.
  Dim row As DataRow
  For i As Integer = 0 To 9
    row = table.NewRow()
    row("item") = "item " & i
    table.Rows.Add(row)
  Next i

  table.AcceptChanges()
  Return table
End Function

Private Sub PrintValues(ByVal table As DataTable, ByVal label As String)
  ' Display the contents of the supplied DataTable:
  Console.WriteLine(label)
  For Each row As DataRow In table.Rows
    For Each column As DataColumn In table.Columns
      Console.Write("{0}{1}", ControlChars.Tab, row(column))
    Next column
    Console.WriteLine()
  Next row
End Sub

備註

電流 DataTable 及其後代會被載入來自所提供 Stream資料的。此方法的行為與該 DataSet.ReadXml 方法相同，不同之處在於資料僅載入目前資料表及其後代資料。

此 ReadXml 方法提供一種僅讀取資料，或同時讀取資料與結構的資料 DataTable ，從 XML 文件中讀取的方法，而該 ReadXmlSchema 方法僅讀取結構。

Note

InvalidOperationException若被讀取或寫IDynamicMetaObjectProvider入的欄位DataRow類型將被拋出，且未實作 IXmlSerializable。

若指定內聯結構，則在載入資料前，內行結構用於擴充現有關聯結構。若存在衝突（例如同一資料表中同一欄位以不同資料型態定義），會提出例外。

若未指定內列結構，則根據 XML 文件的結構，透過推理擴展關聯結構。若無法透過推理擴展結構以暴露所有資料，則會提出例外。

Note

當DataSet序列化 XML 中合法的 XML 字元如「_」逃逸時，也不會將 XML 元素與其對應DataColumnDataTable元素關聯。本身 DataSet 只能逃逸 XML 元素名稱中的非法 XML 字元，因此只能消耗相同的資料。當 XML 元素名稱中的法律字元被逃逸時，該元素在處理過程中會被忽略。

另請參閱

DataTables

適用於

ReadXml(TextReader)

利用指定的 TextReaderXML 結構與資料讀取。DataTable

public:
 System::Data::XmlReadMode ReadXml(System::IO::TextReader ^ reader);

public System.Data.XmlReadMode ReadXml(System.IO.TextReader reader);

member this.ReadXml : System.IO.TextReader -> System.Data.XmlReadMode

Public Function ReadXml (reader As TextReader) As XmlReadMode

參數

reader: TextReader

TextReader那個會用來讀取資料。

傳回

XmlReadMode

他們 XmlReadMode 會讀取資料。

範例

private static void DemonstrateReadWriteXMLDocumentWithReader()
{
    DataTable table = CreateTestTable("XmlDemo");
    PrintValues(table, "Original table");

    // Write the schema and data to XML in a memory stream.
    System.IO.MemoryStream xmlStream = new System.IO.MemoryStream();
    table.WriteXml(xmlStream, XmlWriteMode.WriteSchema);

    // Rewind the memory stream.
    xmlStream.Position = 0;

    System.IO.StreamReader reader =
        new System.IO.StreamReader(xmlStream);
    DataTable newTable = new DataTable();
    newTable.ReadXml(reader);

    // Print out values in the table.
    PrintValues(newTable, "New table");
}

private static DataTable CreateTestTable(string tableName)
{
    // Create a test DataTable with two columns and a few rows.
    DataTable table = new DataTable(tableName);
    DataColumn column = new DataColumn("id", typeof(System.Int32));
    column.AutoIncrement = true;
    table.Columns.Add(column);

    column = new DataColumn("item", typeof(System.String));
    table.Columns.Add(column);

    // Add ten rows.
    DataRow row;
    for (int i = 0; i <= 9; i++)
    {
        row = table.NewRow();
        row["item"] = "item " + i;
        table.Rows.Add(row);
    }

    table.AcceptChanges();
    return table;
}

private static void PrintValues(DataTable table, string label)
{
    Console.WriteLine(label);
    foreach (DataRow row in table.Rows)
    {
        foreach (DataColumn column in table.Columns)
        {
            Console.Write("\t{0}", row[column]);
        }
        Console.WriteLine();
    }
}

Private Sub DemonstrateReadWriteXMLDocumentWithReader()
  Dim table As DataTable = CreateTestTable("XmlDemo")
  PrintValues(table, "Original table")

  ' Write the schema and data to XML in a memory stream.
  Dim xmlStream As New System.IO.MemoryStream()
  table.WriteXml(xmlStream, XmlWriteMode.WriteSchema)

  ' Rewind the memory stream.
  xmlStream.Position = 0

  Dim reader As New System.IO.StreamReader(xmlStream)
  Dim newTable As New DataTable
  newTable.ReadXml(reader)

  ' Print out values in the table.
  PrintValues(newTable, "New Table")
End Sub

Private Function CreateTestTable(ByVal tableName As String) _
  As DataTable
  ' Create a test DataTable with two columns and a few rows.
  Dim table As New DataTable(tableName)
  Dim column As New DataColumn("id", GetType(System.Int32))
  column.AutoIncrement = True
  table.Columns.Add(column)

  column = New DataColumn("item", GetType(System.String))
  table.Columns.Add(column)

  ' Add ten rows.
  Dim row As DataRow
  For i As Integer = 0 To 9
    row = table.NewRow()
    row("item") = "item " & i
    table.Rows.Add(row)
  Next i

  table.AcceptChanges()
  Return table
End Function

Private Sub PrintValues(ByVal table As DataTable, _
  ByVal label As String)
  Console.WriteLine(label)
  For Each row As DataRow In table.Rows
    For Each column As DataColumn In table.Columns
      Console.Write("{0}{1}", ControlChars.Tab, row(column))
    Next column
    Console.WriteLine()
  Next row
End Sub

備註

電流 DataTable 及其後代會被載入來自所提供 TextReader資料的。此方法的行為與該 DataSet.ReadXml 方法相同，不同之處在於資料僅載入目前資料表及其後代資料。

此 ReadXml 方法提供一種僅讀取資料，或同時讀取資料與結構的資料 DataTable ，從 XML 文件中讀取的方法，而該 ReadXmlSchema 方法僅讀取結構。

Note

InvalidOperationException若被讀取或寫IDynamicMetaObjectProvider入的欄位DataRow類型將被拋出，且未實作 IXmlSerializable。

若指定內聯結構，則在載入資料前，內行結構用於擴充現有關聯結構。若存在衝突（例如同一資料表中同一欄位以不同資料型態定義），會提出例外。

若未指定內列結構，則根據 XML 文件的結構，透過推理擴展關聯結構。若無法透過推理擴展結構以暴露所有資料，則會提出例外。

Note

另請參閱

DataTables

適用於

ReadXml(String)

從指定的檔案讀取 XML 架構和資料。DataTable

public:
 System::Data::XmlReadMode ReadXml(System::String ^ fileName);

public System.Data.XmlReadMode ReadXml(string fileName);

member this.ReadXml : string -> System.Data.XmlReadMode

Public Function ReadXml (fileName As String) As XmlReadMode

參數

fileName: String

讀取資料的檔案名稱。

傳回

XmlReadMode

他們 XmlReadMode 會讀取資料。

範例

以下範例會產生包含兩欄十列的。DataTable 範例中將 DataTable 結構和資料寫入磁碟。範例中會建立第二個 DataTable ，並呼叫該 ReadXml 方法來填充結構與資料。

private static void DemonstrateReadWriteXMLDocumentWithString()
{
    DataTable table = CreateTestTable("XmlDemo");
    PrintValues(table, "Original table");

    string fileName = "C:\\TestData.xml";
    table.WriteXml(fileName, XmlWriteMode.WriteSchema);

    DataTable newTable = new DataTable();
    newTable.ReadXml(fileName);

    // Print out values in the table.
    PrintValues(newTable, "New table");
}

private static DataTable CreateTestTable(string tableName)
{
    // Create a test DataTable with two columns and a few rows.
    DataTable table = new DataTable(tableName);
    DataColumn column = new DataColumn("id", typeof(System.Int32));
    column.AutoIncrement = true;
    table.Columns.Add(column);

    column = new DataColumn("item", typeof(System.String));
    table.Columns.Add(column);

    // Add ten rows.
    DataRow row;
    for (int i = 0; i <= 9; i++)
    {
        row = table.NewRow();
        row["item"] = "item " + i;
        table.Rows.Add(row);
    }

    table.AcceptChanges();
    return table;
}

private static void PrintValues(DataTable table, string label)
{
    Console.WriteLine(label);
    foreach (DataRow row in table.Rows)
    {
        foreach (DataColumn column in table.Columns)
        {
            Console.Write("\t{0}", row[column]);
        }
        Console.WriteLine();
    }
}

Private Sub DemonstrateReadWriteXMLDocumentWithString()
  Dim table As DataTable = CreateTestTable("XmlDemo")
  PrintValues(table, "Original table")

  ' Write the schema and data to XML in a file.
  Dim fileName As String = "C:\TestData.xml"
  table.WriteXml(fileName, XmlWriteMode.WriteSchema)

  Dim newTable As New DataTable
  newTable.ReadXml(fileName)

  ' Print out values in the table.
  PrintValues(newTable, "New Table")
End Sub

Private Function CreateTestTable(ByVal tableName As String) _
  As DataTable

  ' Create a test DataTable with two columns and a few rows.
  Dim table As New DataTable(tableName)
  Dim column As New DataColumn("id", GetType(System.Int32))
  column.AutoIncrement = True
  table.Columns.Add(column)

  column = New DataColumn("item", GetType(System.String))
  table.Columns.Add(column)

  ' Add ten rows.
  Dim row As DataRow
  For i As Integer = 0 To 9
    row = table.NewRow()
    row("item") = "item " & i
    table.Rows.Add(row)
  Next i

  table.AcceptChanges()
  Return table
End Function

Private Sub PrintValues(ByVal table As DataTable, _
  ByVal label As String)
  Console.WriteLine(label)
  For Each row As DataRow In table.Rows
    For Each column As DataColumn In table.Columns
      Console.Write("{0}{1}", ControlChars.Tab, row(column))
    Next column
    Console.WriteLine()
  Next row
End Sub

備註

當前 DataTable 檔案及其後代資料會載入所提供 String檔案中命名的檔案資料。此方法的行為與該 DataSet.ReadXml 方法相同，不同之處在於資料僅載入目前資料表及其後代資料。

此 ReadXml 方法提供一種僅讀取資料，或同時讀取資料與結構的資料 DataTable ，從 XML 文件中讀取的方法，而該 ReadXmlSchema 方法僅讀取結構。

Note

InvalidOperationException若被讀取或寫IDynamicMetaObjectProvider入的欄位DataRow類型將被拋出，且未實作 IXmlSerializable。

若指定內聯結構，則在載入資料前，內行結構用於擴充現有關聯結構。若存在衝突（例如同一資料表中同一欄位以不同資料型態定義），會提出例外。

若未指定內列結構，則根據 XML 文件的結構，透過推理擴展關聯結構。若無法透過推理擴展結構以暴露所有資料，則會提出例外。

Note

using System.Data;
public class A {
   static void Main(string[] args) {
      DataTable tabl = new DataTable("mytable");
      tabl.Columns.Add(new DataColumn("id", typeof(int)));
      for (int i = 0; i < 10; i++) {
         DataRow row = tabl.NewRow();
         row["id"] = i;
         tabl.Rows.Add(row);
      }
      tabl.WriteXml("f.xml", XmlWriteMode.WriteSchema);
      DataTable newt = new DataTable();
      newt.ReadXml("f.xml");
   }
}

另請參閱

DataTables

適用於

ReadXml(XmlReader)

利用指定的 XmlReader. 將 XML 架構與資料讀取至DataTable

public:
 System::Data::XmlReadMode ReadXml(System::Xml::XmlReader ^ reader);

public System.Data.XmlReadMode ReadXml(System.Xml.XmlReader reader);

member this.ReadXml : System.Xml.XmlReader -> System.Data.XmlReadMode

Public Function ReadXml (reader As XmlReader) As XmlReadMode

參數

reader: XmlReader

XmlReader那個會用來讀取資料。

傳回

XmlReadMode

他們 XmlReadMode 會讀取資料。

範例

以下範例會產生包含兩欄十列的。DataTable 範例將 DataTable 結構與資料寫入 XmlReader。範例會建立第二個 DataTable ，並呼叫該 ReadXml 方法，將實例中的 XmlReader 結構和資料填入該方法。

private static void DemonstrateReadWriteXMLDocumentWithReader()
{
    DataTable table = CreateTestTable("XmlDemo");
    PrintValues(table, "Original table");

    // Write the schema and data to XML in a memory stream.
    System.IO.MemoryStream xmlStream = new System.IO.MemoryStream();
    table.WriteXml(xmlStream, XmlWriteMode.WriteSchema);

    // Rewind the memory stream.
    xmlStream.Position = 0;

    System.Xml.XmlTextReader reader =
        new System.Xml.XmlTextReader(xmlStream);
    DataTable newTable = new DataTable();
    newTable.ReadXml(reader);

    // Print out values in the table.
    PrintValues(newTable, "New table");
}

private static DataTable CreateTestTable(string tableName)
{
    // Create a test DataTable with two columns and a few rows.
    DataTable table = new DataTable(tableName);
    DataColumn column = new DataColumn("id", typeof(System.Int32));
    column.AutoIncrement = true;
    table.Columns.Add(column);

    column = new DataColumn("item", typeof(System.String));
    table.Columns.Add(column);

    // Add ten rows.
    DataRow row;
    for (int i = 0; i <= 9; i++)
    {
        row = table.NewRow();
        row["item"] = "item " + i;
        table.Rows.Add(row);
    }

    table.AcceptChanges();
    return table;
}

private static void PrintValues(DataTable table, string label)
{
    Console.WriteLine(label);
    foreach (DataRow row in table.Rows)
    {
        foreach (DataColumn column in table.Columns)
        {
            Console.Write("\t{0}", row[column]);
        }
        Console.WriteLine();
    }
}

Private Sub DemonstrateReadWriteXMLDocumentWithReader()
  Dim table As DataTable = CreateTestTable("XmlDemo")
  PrintValues(table, "Original table")

  ' Write the schema and data to XML in a memory stream.
  Dim xmlStream As New System.IO.MemoryStream()
  table.WriteXml(xmlStream, XmlWriteMode.WriteSchema)

  ' Rewind the memory stream.
  xmlStream.Position = 0

  Dim reader As New System.Xml.XmlTextReader(xmlStream)
  Dim newTable As New DataTable
  newTable.ReadXml(reader)

  ' Print out values in the table.
  PrintValues(newTable, "New Table")
End Sub

Private Function CreateTestTable(ByVal tableName As String) _
  As DataTable
  ' Create a test DataTable with two columns and a few rows.
  Dim table As New DataTable(tableName)
  Dim column As New DataColumn("id", GetType(System.Int32))
  column.AutoIncrement = True
  table.Columns.Add(column)

  column = New DataColumn("item", GetType(System.String))
  table.Columns.Add(column)

  ' Add ten rows.
  Dim row As DataRow
  For i As Integer = 0 To 9
    row = table.NewRow()
    row("item") = "item " & i
    table.Rows.Add(row)
  Next i

  table.AcceptChanges()
  Return table
End Function

Private Sub PrintValues(ByVal table As DataTable, _
  ByVal label As String)
  Console.WriteLine(label)
  For Each row As DataRow In table.Rows
    For Each column As DataColumn In table.Columns
      Console.Write("{0}{1}", ControlChars.Tab, row(column))
    Next column
    Console.WriteLine()
  Next row
End Sub

備註

當前 DataTable 檔案及其後代資料會載入所提供 XmlReader檔案中命名的檔案資料。此方法的行為與該 ReadXml 方法相同，不同之處在於資料僅載入目前資料表及其後代資料。

此 ReadXml 方法提供一種僅讀取資料，或同時讀取資料與結構的資料 DataTable ，從 XML 文件中讀取的方法，而該 ReadXmlSchema 方法僅讀取結構。

Note

InvalidOperationException若被讀取或寫IDynamicMetaObjectProvider入的欄位DataRow類型將被拋出，且未實作 IXmlSerializable。

若指定內聯結構，則在載入資料前，內行結構用於擴充現有關聯結構。若存在衝突（例如同一資料表中同一欄位以不同資料型態定義），會提出例外。

若未指定內列結構，則根據 XML 文件的結構，透過推理擴展關聯結構。若無法透過推理擴展結構以暴露所有資料，則會提出例外。

Note

另請參閱

DataTables

適用於

意見反應

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