使用vb.net从SQL Filestream列检索文件

Imports System.Data.SqlClient
Imports System.IO

Public Class FilestreamExample
    Public Sub RetrieveFileFromSQLFilestream()
        ' 建立与SQL Server数据库的连接
        Dim connectionString As String = "Data Source=YourServer;Initial Catalog=YourDatabase;User ID=YourUsername;Password=YourPassword;"
        Dim connection As New SqlConnection(connectionString)
        connection.Open()

        ' SQL查询语句
        Dim query As String = "SELECT FilestreamColumn.PathName() AS FilePath FROM YourTable WHERE YourCondition"

        ' 执行查询
        Dim command As New SqlCommand(query, connection)
        Dim reader As SqlDataReader = command.ExecuteReader()

        ' 读取结果集
        If reader.Read() Then
            ' 获取Filestream列的数据流
            Dim filePath As String = reader("FilePath").ToString()
            Dim fileStream As Stream = reader.GetStream(0)

            ' 将数据流保存到本地文件
            Dim outputFile As String = "C:\Path\To\Save\File.ext"
            Using outputStream As New FileStream(outputFile, FileMode.Create)
                fileStream.CopyTo(outputStream)
            End Using

            ' 其他处理操作...
        End If

        ' 关闭连接
        reader.Close()
        connection.Close()
    End Sub
End Class