将 XML 值指定为参数

如果查询需要值为 XML 字符串的参数，你可以使用 SqlXml 数据类型的实例提供该值。 真的没有任何窍门；SQL Server 中的 XML 列接受参数值的方式与其他数据类型完全相同。

示例

以下控制台应用程序在 AdventureWorks 数据库中新建一个表。 新表包括一个名为 SalesID 的列和一个名为 SalesInfo 的 XML 列。

备注

默认情况下，在安装 SQL Server 时不安装 AdventureWorks 示例数据库。 可以通过运行 SQL Server 安装程序来安装它。

该示例准备一个 SqlCommand 对象以在新表中插入行。 保存的文件为 SalesInfo 列提供所需的 XML 数据。

若要创建运行示例所需的文件，请在与项目相同的文件夹中创建一个新的文本文件。 将文件命名为 MyTestStoreData.xml。 在记事本中打开该文件，然后复制并粘贴以下文本：

<StoreSurvey xmlns="http://schemas.microsoft.com/sqlserver/2004/07/adventure-works/StoreSurvey">
  <AnnualSales>300000</AnnualSales>
  <AnnualRevenue>30000</AnnualRevenue>
  <BankName>International Bank</BankName>
  <BusinessType>BM</BusinessType>
  <YearOpened>1970</YearOpened>
  <Specialty>Road</Specialty>
  <SquareFeet>7000</SquareFeet>
  <Brands>3</Brands>
  <Internet>T1</Internet>
  <NumberEmployees>2</NumberEmployees>
</StoreSurvey>

Imports System
Imports System.Data.SqlClient
Imports System.Data.SqlTypes
Imports System.Xml

Module Module1
    Sub Main()

        Using connection As SqlConnection = New SqlConnection(GetConnectionString())
        connection.Open()

        ' Create a sample table (dropping first if it already
        ' exists.)
        Dim commandNewTable As String = _
         "IF EXISTS (SELECT * FROM dbo.sysobjects " & _
         "WHERE id = object_id(N'[dbo].[XmlDataTypeSample]') " & _
         "AND OBJECTPROPERTY(id, N'IsUserTable') = 1) " & _
         "DROP TABLE [dbo].[XmlDataTypeSample];" & _
         "CREATE TABLE [dbo].[XmlDataTypeSample](" & _
         "[SalesID] [int] IDENTITY(1,1) NOT NULL, " & _
         "[SalesInfo] [xml])"

        Dim commandAdd As New _
         SqlCommand(commandNewTable, connection)
        commandAdd.ExecuteNonQuery()

        Dim commandText As String = _
         "INSERT INTO [dbo].[XmlDataTypeSample] " & _
           "([SalesInfo] ) " & _
           "VALUES(@xmlParameter )"

        Dim command As New SqlCommand(commandText, connection)

        ' Read the saved XML document as a
        ' SqlXml-data typed variable.
        Dim newXml As SqlXml = _
         New SqlXml(New XmlTextReader("MyTestStoreData.xml"))

        ' Supply the SqlXml value for the value of the parameter.
        command.Parameters.AddWithValue("@xmlParameter", newXml)

        Dim result As Integer = command.ExecuteNonQuery()
        Console.WriteLine(result & " row was added.")
        Console.WriteLine("Press Enter to continue.")
        Console.ReadLine()
    End Using
End Sub

    Private Function GetConnectionString() As String
        ' To avoid storing the connection string in your code,
        ' you can retrieve it from a configuration file.
        Return "..."
    End Function
End Module

using System;
using System.Data;
using System.Data.SqlClient;
using System.Xml;
using System.Data.SqlTypes;

class Class1
{
    static void Main()
    {
        using (SqlConnection connection = new SqlConnection(GetConnectionString()))
       {
        connection.Open();
        //  Create a sample table (dropping first if it already
        //  exists.)

        string commandNewTable =
            "IF EXISTS (SELECT * FROM dbo.sysobjects " +
            "WHERE id = " +
                  "object_id(N'[dbo].[XmlDataTypeSample]') " +
            "AND OBJECTPROPERTY(id, N'IsUserTable') = 1) " +
            "DROP TABLE [dbo].[XmlDataTypeSample];" +
            "CREATE TABLE [dbo].[XmlDataTypeSample](" +
            "[SalesID] [int] IDENTITY(1,1) NOT NULL, " +
            "[SalesInfo] [xml])";
        SqlCommand commandAdd =
                   new SqlCommand(commandNewTable, connection);
        commandAdd.ExecuteNonQuery();
        string commandText =
            "INSERT INTO [dbo].[XmlDataTypeSample] " +
            "([SalesInfo] ) " +
            "VALUES(@xmlParameter )";
        SqlCommand command =
                  new SqlCommand(commandText, connection);

        //  Read the saved XML document as a
        //  SqlXml-data typed variable.
        SqlXml newXml =
            new SqlXml(new XmlTextReader("MyTestStoreData.xml"));

        //  Supply the SqlXml value for the value of the parameter.
        command.Parameters.AddWithValue("@xmlParameter", newXml);

        int result = command.ExecuteNonQuery();
        Console.WriteLine(result + " row was added.");
        Console.WriteLine("Press Enter to continue.");
        Console.ReadLine();
    }
  }

    private static string GetConnectionString()
    {
        // To avoid storing the connection string in your code,
        // you can retrieve it from a configuration file.
        return "...";
    }
}

请参阅

• SqlXml
• SQL Server 中的 XML 数据
• ADO.NET 概述