（一）
写入：
Stream ms;
byte []picbyte;
openFileDialog1.Filter = SystemConst.IMAGE_FILE_FILTER;
if (this.openFileDialog1.ShowDialog() == DialogResult.OK)
{
if ((ms = openFileDialog1.OpenFile()) != null)
{
picbyte = new byte[ms.Length];
ms.Position = 0;
ms.Read(picbyte, 0, Convert.ToInt32(ms.Length));
ms.Dispose();
}
}
得到picbyte[] 后就可以插入数据库了。对应数据库的Image类型
读取：
if (dt.Rows[0]["Photo"] != DBNull.Value)
{
byte[] mybyte = (byte[])dt.Rows[0]["Photo"];
MemoryStream ms = new MemoryStream(mybyte );
this.pb_Employee.Image = Image.FromStream(ms, true);
}
（二）
存：
SqlConnection con = new SqlConnection("Server=Darkover;uid=<username>;pwd=<strong password>;database=northwind");
SqlDataAdapter da = new SqlDataAdapter("Select * From MyImages", con);
SqlCommandBuilder MyCB = new SqlCommandBuilder(da);
DataSet ds = new DataSet("MyImages");
da.MissingSchemaAction = MissingSchemaAction.AddWithKey;
FileStream fs = new FileStream(@"C:\winnt\Gone Fishing.BMP", FileMode.OpenOrCreate, FileAccess.Read);
byte[] MyData= new byte[fs.Length];
fs.Read(MyData, 0, System.Convert.ToInt32(fs.Length));
fs.Close();
da.Fill(ds,"MyImages");
DataRow myRow;
myRow=ds.Tables["MyImages"].NewRow();
myRow["Description"] = "This would be description text";
myRow["imgField"] = MyData;
ds.Tables["MyImages"].Rows.Add(myRow);
da.Update(ds, "MyImages");
con.Close();
取：
SqlConnection con = new SqlConnection("Server=Darkover;uid=<username>;pwd=<strong password>;database=northwind");
SqlDataAdapter da = new SqlDataAdapter("Select * From MyImages", con);
SqlCommandBuilder MyCB = new SqlCommandBuilder(da);
DataSet ds = new DataSet("MyImages");
byte[] MyData= new byte[0];
da.Fill(ds, "MyImages");
DataRow myRow;
myRow=ds.Tables["MyImages"].Rows[0];
MyData = (byte[])myRow["imgField"];
int ArraySize = new int();
ArraySize = MyData.GetUpperBound(0);
FileStream fs = new FileStream(@"C:\winnt\Gone Fishing2.BMP", FileMode.OpenOrCreate, FileAccess.Write);
fs.Write(MyData, 0,ArraySize);
fs.Close();
（三）
添加图片
OleDbConnection mycnn=new OleDbConnection("provider=Microsoft.jet.oledb.4.0;data source=f:\\dazhu.mdb");
mycnn.Open();
OleDbCommand mycmd=new OleDbCommand("update info set picture=@a",mycnn );
FileStream mystream=new FileStream("f:\\1.jpg",FileMode.Open,FileAccess.Read);
long len=mystream.Length;
mycmd.Parameters.Add("@a",OleDbType.Binary,(int)len,"picture");
mycmd.Parameters["@a"].Direction=System.Data.ParameterDirection.Input;
byte []box=new byte[len];
mystream.Read(box,0,(int)len);
mycmd.Parameters["@a"].Value=box;
//更新
mycmd.ExecuteNonQuery();
MessageBox.Show("ok");
mystream.Close();
mycnn.Close();
读取图片
OleDbConnection mycnn=new OleDbConnection("provider=Microsoft.jet.oledb.4.0;data source=f:\\dazhu.mdb");
mycnn.Open();
MessageBox.Show("ok.mycnn.open");
OleDbCommand mycmd=new OleDbCommand("select * from info",mycnn );
OleDbDataReader myrd=mycmd.ExecuteReader();
if(myrd.Read())
{
byte []box=(byte [])myrd["picture"];
Stream stream1=new MemoryStream(box);
this.pictureBox2.Image=System.Drawing.Image.FromStream(stream1);
stream1.Close();
}
mycnn.Close();
（四）
//选择图片，并显示
private void menuItem4_Click(object sender, System.EventArgs e)
{
dlgAddPic.Filter="JPEG 图像文件（*.jpg;*.jpeg）|*.jpg;*.jpeg|Windows 位图文件（*.bmp）|*.bmp|GIF 计算机服务（*.gif）|*.gif|所有文件（*.*）|*.*";
if (dlgAddPic.ShowDialog()==DialogResult.OK)
{
if (picSmall.Image != null)
{
picSmall.Image.Dispose();
picBig.Image.Dispose();
picSmall.Image=null;
picBig.Image=null;
}
picSmall.Image=Image.FromFile(dlgAddPic.FileName);
picBig.Image=Image.FromFile(dlgAddPic.FileName);
txtPicName.Text=dlgAddPic.FileName.Substring(dlgAddPic.FileName.LastIndexOf(@"\",dlgAddPic.FileName.Length,dlgAddPic.FileName.Length)+1);
}
}
//保存，添加到数据库
private void menuItem15_Click(object sender, System.EventArgs e)
{
if (cboPicType.Text=="")
{
MessageBox.Show("请确定图片类别！");
return;
}
MemoryStream mStream =new MemoryStream();
try
{
if (txtPicName.Text.Length<5) return;
switch(txtPicName.Text.Substring(txtPicName.Text.Length-3).ToUpper())
{
case "JPG":
case "PEG":
picBig.Image.Save(mStream,ImageFormat.Jpeg);
picBig.Image.Save()
break;
case "GIF":
picBig.Image.Save(mStream,ImageFormat.Gif);
break;
case "BMP":
picBig.Image.Save(mStream,ImageFormat.Bmp);
break;
}
}
catch(Exception ex)
{
MessageBox.Show(ex.Message);
}
byte[] picData=new byte[mStream.Length];
mStream.Position=0;
mStream.Read(picData,0,Convert.ToInt32(mStream.Length));
mStream.Close();
mStream=null;
string strInsertSQL="insert into "+cboPicType.Text+" (NAME , PIC) values('"+txtPicName.Text+picData.Length.ToString()+"' ,@pic)";
cmd.CommandText=strInsertSQL;
OleDbParameter paramPic=new OleDbParameter("@pic",OleDbType.VarBinary);
paramPic.SourceColumn="PIC";
paramPic.Value=picData;
cmd.Parameters.Clear();
cmd.Parameters.Add(paramPic);
try
{
cmd.ExecuteNonQuery();
MessageBox.Show("添加成功！");
string strSQL="select top 1 ID from "+cboPicType.Text+" order by ID desc";
cmd.CommandText=strSQL;
cboPicID.Items.Add(cmd.ExecuteScalar().ToString());
}
catch(Exception ex)
{
MessageBox.Show(ex.Message);
}
（五）
//照片輸入數據庫
try
{
if(path!="")
{
FileInfo fi=new FileInfo(path);
int imgdatalen=Convert.ToInt32(fi.Length);
byte[] imadata=new byte[imgdatalen];
Stream imgdatastream=fi.OpenRead();
imgdatastream.Read(imadata,0,imgdatalen);
emp.ZP=imadata;
}
}
catch(Exception ee)
{
MessageBox.Show(ee.Message.ToString());
}
點擊picturebox瀏覽圖片：
private void pictureBox1_Click(object sender, System.EventArgs e)
{
try
{
Bitmap MyImage;
OpenFileDialog open=new OpenFileDialog();
open.ShowDialog();
path=open.FileName;
if(path=="")
{
return;
}
pictureBox1.SizeMode = PictureBoxSizeMode.StretchImage ;
MyImage = new Bitmap(path);
pictureBox1.ClientSize = new Size(pictureBox1.Width,pictureBox1.Height);
pictureBox1.Image = (Image) MyImage ;
}
catch(Exception ee)
{
MessageBox.Show(ee.Message.ToString());
}