如何将上传图片和文字写进数据库

图片放在本地的某个目录中如“c:\image”，然后再把这个目录+图片名存入数据库"c:\image\image1.jpg"。读出时只要使用<img

href="c:\image\image1.jpg">就OK了。除此之外还可以把上传的图片作为字节流读入数据库，读出时使用cgi或Servlet程序把读出的流以图片显示出来。

首先，在数据库中要建立相应的字段能保存Bytes，例如在SQL Server中用Image类型来定义字段。我所用到的数据库大致结构如下：

字段名

类型

备注

FileID

Int

自增字段

FileName

Varchar(256)

FullName

Varchar(1024)

FileData

Image

然后就是写入数据库，代码如下：

FileInfo fi = new FileInfo( txtFileName.Text )// Replace with your file name

if ( fi.Exists)

{

byte[] bData = null

int nNewFileID = 0

// Read file data into buffer

using ( FileStream fs = fi.OpenRead() )

{

bData = new byte[fi.Length]

int nReadLength = fs.Read( bData,0, (int)(fi.Length) )

}

// Add file info into DB

string strQuery = "INSERT INTO FileInfo "

+ " ( FileName, FullName, FileData ) "

+ " VALUES "

+ " ( @FileName, @FullName, @FileData ) "

+ " SELECT @@IDENTITY AS 'Identity'"

SqlCommand sqlComm = new SqlCommand( strQuery, sqlConn )

sqlComm.Parameters.Add( "@FileName", fi.Name )

sqlComm.Parameters.Add( "@FullName", fi.FullName )

sqlComm.Parameters.Add( "@FileData", bData )

// Get new file ID

SqlDataReader sqlReader = sqlComm.ExecuteReader()

if( sqlReader.Read() )

{

nNewFileID = int.Parse(sqlReader.GetValue(0).ToString())

}

sqlReader.Close()

sqlComm.Dispose()

if( nNewFileID >0 )

{

// Add new item in list view

ListViewItem itmNew = lsvFileInfo.Items.Add( fi.Name )

itmNew.Tag = nNewFileID

}

}

而读出的代码如下：

// Get new file name

string strFullName = dlgFBSave.SelectedPath

if( strFullName[strFullName.Length - 1] != '\\' )

strFullName += @"\"

strFullName += lsvFileInfo.SelectedItems[0].Text

string strQuery = "SELECT FileData FROM FileInfo "

+ " WHERE FileID = " + lsvFileInfo.SelectedItems[0].Tag.ToString()

SqlDataAdapter sqlDAdapter = new SqlDataAdapter(strQuery,sqlConn)

DataSet sqlRecordSet = new DataSet()

byte[] bData = null

//Get file data from DB

try

{

sqlDAdapter.Fill( sqlRecordSet, "FileInfo" )

foreach( DataRow dr in sqlRecordSet.Tables["FileInfo"].Rows)

{

if( dr["FileData"] != DBNull.Value )

bData = ( byte[] )dr["FileData"]

}

}

catch(SqlException sqlErr)

{

MessageBox.Show( sqlErr.Message )

}

catch

{

MessageBox.Show( "Failed to read data from DB!" )

}

sqlRecordSet.Dispose()

sqlDAdapter.Dispose()

if( bData != null )

{

// Save file

FileInfo fi = new FileInfo( strFullName )

if( !fi.Exists )

{

//Create the file.

using (FileStream fs = fi.Create())

{

fs.Write( bData, 0, bData.Length)

}

}

else

{

//Create the file.

using (FileStream fs = fi.OpenWrite())

{

fs.Write( bData, 0, bData.Length)

}

}

}

不过需要提的一点，如果把大量的文件存入数据库的话，会造成数据库的臃肿，而且访问量也会增大。所以现在比较流行的做法，是把文件上传到服务器上，而在数据库上只保存文件的相对路径即可。那么访问的时候，先通过数据库得到文件的相对路径，然后再访问服务器上的文件

插入： //单击图片选择添加的图片 private void pic_Click(object sender, EventArgs e)

{ dlg.Filter = "JPG|*.jpg|BMP|*.bmp|PNG|*.png"

if (dlg.ShowDialog() == System.Windows.Forms.DialogResult.OK)

{

pic.Image = Image.FromFile(dlg.FileName)

txtFilePath = dlg.FileName

}

} public byte[] picData public string txtFilePath = "" 添加确定按钮代码： f (txtFilePath != "")

{

try

{

FileStream fs = new FileStream(txtFilePath, FileMode.Open, FileAccess.Read)

int len = Convert.ToInt32(fs.Length)

b = new byte[len]

fs.Read(b, 0, len)

fs.Close()

}

catch

{

b = null

}

}SqlConnection conn = new SqlConnection(strConn)

conn.Open()SqllCommand cmdInsert = new SqlCommand()

cmdInsert.Connection = conn

cmdInsert.CommandText =插入语句；cmdInsert.Parameters.Add("@照片", SqlDbType.Image) if (txtFilePath == "")

{

cmdInsert.Parameters["@照片"].Value = DBNull.Value

}

else

{

cmdInsert.Parameters["@照片"].Value = b

}

cmdInsert.ExecuteNonQuery()

conn.Close()获取: public byte[] picDataSqlConnection conn = new SqlConnection(strConn)

SqlCommand cmd = new SqlCommand()

cmd.Connection = conn

cmd.CommandText = "select * from 联系人 where 编号=" + ID.ToString()

SqlDataAdapter sda = new SqlDataAdapter(cmd)

DataSet ds = new DataSet()sda.Fill(ds) if (ds.Tables[0].Rows.Count == 1)

{

if (ds.Tables[0].Rows[0]["照片"] == DBNull.Value)

{ //pic为picturebox控件

pic.Image = PhoneBoook.Properties.Resources.DeskShade//为空的话给个默认图片

}

else

{

byte[] b = (byte[])(ds.Tables[0].Rows[0]["照片"])

pic.Image = Image.FromStream(new MemoryStream(b))

picData = b

}

}

---