如何添加一个文件到xml里面，然后从这个xml里面读取添加的文件，把这个文件存入数据库ms sql server，之后再重数据库中读出这个文件，还原这个文件

[klan]

我有一个文件，可以是任何类型的，exe，jpg或者pdf。
现在我要利用xml，把这个文件转换成这样的格式
<?xml version="1.0" encoding="utf-8" ?>
<data>5HUGs4lkao2k0siakmmampaiena</data>

之后，程序读取这个xml，提出5HUGs4lkao2k0siakmmampaiena存入数据库的表里面。

最后就是程序，去读数据库，把文件再还原，存成文件到c盘。

具体这个文件怎么转换成类似5HUGs4lkao2k0siakmmampaiena这样的编码，以及如何将之存入数据库和读出来还原文件，我不知道该如何写。希望高手贴出相关代码。

反正终归就是读文件成二进制，转换，然后添加到xml里面，存入数据库，读出数据，还原文件。

谢谢

[lemong]

binary stream

[wartim]

序列化和反序列化

[gooood]

System.Text.UnicodeEncoding converter = new System.Text.UnicodeEncoding();
byte[] inputBytes =converter.GetBytes(inputString);
string inputString = converter.GetString(inputBytes);

string inputString = System.Convert.ToBase64String(inputBytes);
byte[] inputBytes = System.Convert.FromBase64String(inputString);

[Jobobo]

不太清楚编码和解码是怎么回事，不过数据库存储可以使用sql server中的xml数据类型，直接写入xml就行了。

[tylike]

http://dotnet.saike.org/article/ebd43e74-1bde-43aa-deaf-211fa24a7bc2/read.aspx
把图象文件转换成XML格式文件
作者：孟宪会 出自：【孟宪会之精彩世界】 发布日期：2003年8月31日 2点3分31秒
--------------------------------------------------------------------------------

利用.NET 框架下的FromBase64String和ToBase64String方法可以很容易地实现图象文件和XML文件的互换。这样可以轻易解决以XML格式保存图片的问题。代码如下：

Public Class Form1
Inherits System.Windows.Forms.Form

#Region " Windows 窗体设计器生成的代码 "
Public Sub New()
MyBase.New()
InitializeComponent()
'在 InitializeComponent() 调用之后添加任何初始化
End Sub

'窗体重写处置以清理组件列表。
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub

'Windows 窗体设计器所必需的
Private components As System.ComponentModel.IContainer
'注意：以下过程是 Windows 窗体设计器所必需的
'可以使用 Windows 窗体设计器修改此过程。
'不要使用代码编辑器修改它。
Friend WithEvents Button1 As System.Windows.Forms.Button
Friend WithEvents Button2 As System.Windows.Forms.Button
Friend WithEvents PictureBox1 As System.Windows.Forms.PictureBox
Friend WithEvents Button3 As System.Windows.Forms.Button
Friend WithEvents Label1 As System.Windows.Forms.Label
Friend WithEvents Label2 As System.Windows.Forms.Label
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
Me.Button1 = New System.Windows.Forms.Button()
Me.Button2 = New System.Windows.Forms.Button()
Me.PictureBox1 = New System.Windows.Forms.PictureBox()
Me.Button3 = New System.Windows.Forms.Button()
Me.Label1 = New System.Windows.Forms.Label()
Me.Label2 = New System.Windows.Forms.Label()
Me.SuspendLayout()
'
'Button1
'
Me.Button1.Location = New System.Drawing.Point(365, 63)
Me.Button1.Name = "Button1"
Me.Button1.Size = New System.Drawing.Size(115, 23)
Me.Button1.TabIndex = 0
Me.Button1.Text = "将图象保存成XML"
'
'Button2
'
Me.Button2.Location = New System.Drawing.Point(365, 98)
Me.Button2.Name = "Button2"
Me.Button2.Size = New System.Drawing.Size(115, 23)
Me.Button2.TabIndex = 1
Me.Button2.Text = "从XML中得到图象"
'
'PictureBox1
'
Me.PictureBox1.Location = New System.Drawing.Point(18, 6)
Me.PictureBox1.Name = "PictureBox1"
Me.PictureBox1.Size = New System.Drawing.Size(320, 460)
Me.PictureBox1.TabIndex = 2
Me.PictureBox1.TabStop = False
'
'Button3
'
Me.Button3.Location = New System.Drawing.Point(365, 28)
Me.Button3.Name = "Button3"
Me.Button3.Size = New System.Drawing.Size(115, 23)
Me.Button3.TabIndex = 3
Me.Button3.Text = "浏览图片…"
'
'Label1
'
Me.Label1.Location = New System.Drawing.Point(369, 135)
Me.Label1.Name = "Label1"
Me.Label1.Size = New System.Drawing.Size(105, 95)
Me.Label1.TabIndex = 4
'
'Label2
'
Me.Label2.Location = New System.Drawing.Point(367, 437)
Me.Label2.Name = "Label2"
Me.Label2.Size = New System.Drawing.Size(130, 16)
Me.Label2.TabIndex = 5
Me.Label2.Text = "【孟宪会之精彩世界】"
'
'Form1
'
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(500, 480)
Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.Label2, Me.Label1, Me.Button3, Me.PictureBox1, Me.Button2, Me.Button1})
Me.Name = "Form1"
Me.Text = "图象文件和XML格式文件互换例子"
Me.ResumeLayout(False)

End Sub

#End Region

Private MyFile As String = ""
Private MyFileExt As String = ""
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
Handles Button2.Click
Dim pic As String
Dim MyXml As System.Xml.XmlDocument = New System.Xml.XmlDocument()
MyXml.Load("c:\MyPhoto.xml")
Dim picNode As System.Xml.XmlNode
picNode = MyXml.SelectSingleNode("/pic/photo")
pic = picNode.InnerText
Dim memoryStream As System.IO.MemoryStream
memoryStream = New System.IO.MemoryStream(Convert.FromBase64String(pic))
Me.PictureBox1.Image = New System.Drawing.Bitmap(memoryStream)
memoryStream.Close()
End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
Handles Button1.Click
If MyFile = "" Then
MessageBox.Show("请选择一个图片！", "错误", MessageBoxButtons.OK, MessageBoxIcon.Warning)
Exit Sub
End If
Dim MyImg As System.Drawing.Image = MyImg.FromFile(MyFile)
Dim memoryStream As System.IO.MemoryStream = New System.IO.MemoryStream()
MyImg.Save(memoryStream, GetImageType(MyFileExt))
Dim b() As Byte
b = memoryStream.GetBuffer()
Dim pic As String = Convert.ToBase64String(b)
memoryStream.Close()
Dim MyXml As System.Xml.XmlDocument = New System.Xml.XmlDocument()
MyXml.LoadXml("<pic><name>孟宪会</name><photo>" + pic + "</photo></pic>")
MyXml.Save("c:\MyPhoto.xml")
Label1.Text = "文件被保存到了：" + Microsoft.VisualBasic.ChrW(13) + "c:\MyPhoto.xml"
End Sub

Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
Handles Button3.Click
Dim openFileDialog1 As New OpenFileDialog()
openFileDialog1.InitialDirectory = "c:\"
openFileDialog1.Filter = "PNG(*.png)|*.png|Gif(*.gif)|*.gif|Jpg(*.jpg)|*.jpg|所有图象文件(*.*)|*.*"
openFileDialog1.FilterIndex = 2
openFileDialog1.RestoreDirectory = True
If openFileDialog1.ShowDialog() = DialogResult.OK Then
MyFile = openFileDialog1.FileName()
MyFileExt = MyFile.Substring(MyFile.LastIndexOf(".") + 1)
End If
End Sub

Public Function GetImageType(ByVal str As String) As System.Drawing.Imaging.ImageFormat
Select Case str.ToLower()
Case "jpg"
Return System.Drawing.Imaging.ImageFormat.Jpeg
Case "gif"
Return System.Drawing.Imaging.ImageFormat.Gif
Case "tiff"
Return System.Drawing.Imaging.ImageFormat.Tiff()
Case "icon"
Return System.Drawing.Imaging.ImageFormat.Icon
Case "image/png"
Return System.Drawing.Imaging.ImageFormat.Png
Case Else
Return System.Drawing.Imaging.ImageFormat.MemoryBmp
End Select
End Function

Private Sub Form1_Closing(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) _
Handles MyBase.Closing
System.Diagnostics.Process.Start("IExplore.exe", "http://xml.sz.luohuedu.net/")
End Sub
End Class

[liyings1002]

我是画了一个按钮，我想点下这个按钮然后把图片读取出来。谁能给我说下具体的吗?