可不可以把图片保存在sqlserver内？？

将uploadfile.postedfile.inputstream保存到一个字节数组中，然后用字节数组做参数传给
command.parameter就可以了。

可以，以二进制数据的形式。
俺实现过vb.ent的代码……

当然可以！使用image字段或者可以保存2进制类型的字段，在使用byte[]将数据写进去就可以了

http://www.dotnetjunkies.com/Article/C4A2ACC3-C6B4-4E4C-802A-85B8DBEC7F25.dcik

如何把图片上传到数据库中并显示出来？imgupload.aspx
<%@ Page EnableSessionState="false" explicit="true" strict="true" MaintainState="false"%>
<%@Import Namespace="System.Data.Sql" %>
<%@Import Namespace="System.IO"%>
   <script language="VB" runat=server>
       Sub UploadBtn_Click(Sender as Object, E as EventArgs)
Dim imgStream as Stream
Dim imgLen as Integer
Dim imgName_value as string
Dim imgContentType as String
Dim imgUploadedName as String----------------------------------------------------------------------------------------------------------------
imgStream = UploadFile.PostedFile.InputStream
                          ' 处理图片数据流
imgLen = UploadFile.PostedFile.ContentLength
                          ' 获知要创建多长的字节数组
imgUploadedName = UploadFile.PostedFile.FileName
Dim imgBinaryData(imgLen) as Byte
                          ' 创建一个字节数组
imgContentType = UploadFile.PostedFile.ContentType
                          ' 处理图片数据类型,如image/gif或image/jpeg
imgName_value = imgName.Value
                          ' 给图片做一个切题的说明(这样,数据库的图片就有两个名字了).一个是上传时原本的文件名,另一个是用户在上传时输入的说明.如果这个说明在上传时没有输入,我们将通过UploadFile.PostedFile.FileName.检索该图片原本的文件名.但是, UploadFile.PostedFile.FileName.返回的是上传图片的完整路径,如可能是: C:\intels\chunfeng.jpg,因此,在稍后我们还要写一个函数来处理一下
Try
If imgName_value.Length < 1 then
imgName_value = GetLastRightOf("\",imgUploadedName )
End if
Catch myEx as Exception
imgName_value = GetLastRightOf("\",imgUploadedName )
End Try
----------------------------------------------------------------------------------------------------------------         Dim  n as Integer = imgStream.Read(imgBinaryData, 0, imgLen)
                 ' 处理图片数据流,并把它转换为一个字节数组
Dim NumRowsAffected as Integer = MyDatabaseMethod(imgName_value, imgBinaryData, imgContentType)
            If NumRowsAffected > 0 then
            Response.Write ( "<BR>恭喜,图片上传成功!" )
Else
            Response.Write ( "<BR> 噢,图片上传失败!" )
End if

End Sub----------------------------------------------------------------------------------------------------------------
' 这个函数就是刚才上面提到的处理形如: C:\intels\chunfeng.jpg文件名的函.GetLastRightOf ()在最后位置寻找"\",一旦定位，就储存到变量 StrPos里,调用SubString()字符串对象方法,并返回在最后那个"\"后面的一切字符.调用String.SubString()应该是SubString(StrPos + 1),因为"\"的长度也要说明,所以要把StrPos加1
        Function GetLastRightOf(LookFor as String, myString as String) as String
Dim StrPos as Integer
StrPos = myString.LastIndexOf(LookFor)
Return myString.SubString(StrPos + 1)
        End Function

----------------------------------------------------------------------------------------------------------------
' 当数据提交,要分析二进制数据并插入到数据库中去,因此,我们需要两个函数来完成:连接字符串和插入图片到数据库.这是后者,可在查询中定义参数哦
        Function MyDatabaseMethod(imgName As String, imgbin As Byte(), imgcontenttype as String) As Integer
            Dim connection as New SQLConnection( sqlConnString() )
            Dim command as New SQLCommand( "INSERT INTO Image (img_name,img_data,img_contenttype) VALUES ( @img_name, @img_data,@img_contenttype )", connection )
            ' 参数img_name是图片说明或名称; img_data是二进制或字节数组; img_contenttype是图片数据类型,如image/gif或image/jpeg
            Dim param0 As New SQLParameter( "@img_name", SQLDataType.VarChar,50 )
            param0.Value = imgName
            command.Parameters.Add( param0 )

            Dim param1 as New SQLParameter( "@img_data", SQLDataType.Image )
            param1.Value = imgbin
            command.Parameters.Add( param1 )

            Dim param2 as New SQLParameter( "@img_contenttype", SQLDataType.VarChar,50 )
            param2.Value = imgcontenttype
            command.Parameters.Add( param2 )
connection.Open()
' 打开一个到数据库的连接
Dim numRowsAffected as Integer = command.ExecuteNonQuery()
' 通过调用command.ExecuteNonQuery()执行命令
            connection.Close()

            Return numRowsAffected

        End Function    ---------------------------------------------------------------------------------------------------------------
Private Function    sqlConnString() as String
        REM -- Get Connstring from config.web
        Dim Context as HttpContext = HttpContext.Current
        Dim AppSettings as HashTable = Ctype(Context.GetConfig("appsettings"),HashTable)
        Dim myDSN as String = Ctype(AppSettings("cnTest"),String)
        Return myDSN
        ' 这个函数很简单:读取数据库连接字符串
    End Function
---------------------------------------------------------------------------------------------------------------    </script>
<html>
<title>精彩春风之上传图片到数据库</title>
<body>----------------------------------------------------------------------------------------------------------------
'建立上传图片的表格
<form enctype="multipart/form-data" runat=server id=form1 name=form1>
' enctype属性向浏览器和服务器说明上传二进制数据
请输入图片说明:
<input type=text id=imgName runat="server" />
'type=text控制一个对话框给用户
<br>选择上传的图片:
    <input id="UploadFile" type=file runat=server>
    <asp:button Text="上传" OnClick="UploadBtn_Click" runat=server/>
</form>
----------------------------------------------------------------------------------------------------------------  </body>
</html>imgview.aspx
<%@ Page EnableSessionState="false" explicit="true"  MaintainState="false"%>
<%@ Import Namespace="System.Data.Sql" %>
<script language="VB" runat="server">
Sub Page_Load(sender As Object, e As EventArgs)
Dim imgid as String = Request.QueryString("id")
Dim sqlText as String = "SELECT img_name, img_contenttype, img_data FROM image WHERE img_pk=" & imgid
Dim dbRead AS SQLDataReader
Dim sqlCmd AS SQLCommand
sqlCmd = New SQLCommand(sqlText,sqlConnString() )
sqlCmd.ActiveConnection.Open()
sqlCmd.execute(dbRead )
If  dbRead.Read()
Response.ContentType = dbRead.Item("img_contenttype").ToString()
Response.BinaryWrite ( dbRead.Item("img_data") )
End If
End Sub
    Private Function    sqlConnString() as String
        ' 从config.web 中获取Connstring from
        Dim Context as HttpContext = HttpContext.Current
        Dim AppSettings as HashTable = Ctype(Context.GetConfig("appsettings"),HashTable)
        Dim myDSN as String = Ctype(AppSettings("cnTest"),String)
        Return myDSN
    End Function
</script>image.sql
if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[image]') and OBJECTPROPERTY(id, N'IsUserTable') = 1)
drop table [dbo].[image]
GO
CREATE TABLE [dbo].[image] (
[img_pk] [int] IDENTITY (1, 1) NOT NULL ,
         //主关键字
[img_name] [varchar] (50) NULL ,
         //图片说明
[img_data] [image] NULL ,
         //储存二进制图像数据
[img_contenttype] [varchar] (50) NULL
         //图片数据分类类型,如"image/gif"或"image/jpeg",以便客户端识别
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO
ALTER TABLE [dbo].[image] WITH NOCHECK ADD
CONSTRAINT [PK_image] PRIMARY KEY  NONCLUSTERED
(
[img_pk]
)  ON [PRIMARY]
GO

存和读private void button1_Click(object sender, System.EventArgs e)
{
FileStream fs = new FileStream("遗迹.jpg",FileMode.Open,FileAccess.Read);
byte[] bytes = new byte[fs.Length];
fs.Read(bytes,0,(int)fs.Length);
string sql = "insert TestFiles(MyFileName,FileType,MyFile)values(@FN,@FT,@MF)";
SqlCommand com = new SqlCommand(sql,this.sqlCon);
SqlParameter FN = new SqlParameter("@FN",SqlDbType.VarChar);
FN.Value = "遗迹";
com.Parameters.Add(FN);
SqlParameter FT = new SqlParameter("@FT",SqlDbType.VarChar);
FT.Value = "JPG";
com.Parameters.Add(FT);
SqlParameter MF = new SqlParameter("@MF",SqlDbType.Image);
MF.Value = bytes;
com.Parameters.Add(MF);
com.CommandType = CommandType.Text;

sqlCon.ConnectionString = this.conStr;
try
{
sqlCon.Open();
com.ExecuteNonQuery();
sqlCon.Close();
MessageBox.Show("存入成功！");
}
catch(Exception ex)
{
throw ex;
}
finally
{
sqlCon.Close();
}
} private void button2_Click(object sender, System.EventArgs e)
{
string sql = "select MyFile from TestFiles where id = 1";

sqlCon.ConnectionString = this.conStr; SqlCommand readComm = new SqlCommand(sql,this.sqlCon); SqlDataReader dr = null; FileStream fs = null; BinaryWriter bw = null; int bufferSize = 100; byte[] outbyte = new byte[bufferSize]; long retval; long startIndex = 0;
try
{
sqlCon.Open();
dr = readComm.ExecuteReader();
while(dr.Read())
{
fs = new FileStream("TakeOut.jpg",FileMode.OpenOrCreate,FileAccess.Write); bw = new BinaryWriter(fs); retval = dr.GetBytes(0, startIndex, outbyte, 0, bufferSize);

while (retval == bufferSize)
{
bw.Write(outbyte);
bw.Flush();

startIndex += bufferSize;
retval = dr.GetBytes(0, startIndex, outbyte, 0, bufferSize);
} // Write the remaining buffer.
bw.Write(outbyte, 0, (int)retval - 1);
bw.Flush(); // Close the output file.
bw.Close();
fs.Close();

Image im = Image.FromFile("TakeOut.jpg"); this.pictureBox1.Image = im;
}
sqlCon.Close();
}
catch(Exception ex)
{
throw ex;
}
finally
{
sqlCon.Close();
bw.Close();
fs.Close();
}
}

这样添加到数据库中的图片是否可以修改呢？比如利用update用另一章图片的二进制覆盖这一图片呢？

调试易

可不可以把图片保存在sqlserver内？？

解决方案 »