图片的上传，存入数据库，显示

1.上传

void submitinfo(Object sender,EventArgs e)
{
 int size=307200;
 int LimitWidth=120;
 int LimitHeight=160;
  try
        {
            if (FileUpload1.PostedFile.FileName == "")         
            {
                //this.Upload_info.Text = "请选择上传文件！";
                Response.Write("请选择上传文件！");
            }
            else
            {
                string filepath = FileUpload1.PostedFile.FileName; //得到的是文件的完整路径,包括文件名，如：C:\Documents and Settings\Administrator\My Documents\My Pictures\20022775_m.jpg
               // Response.Write(filepath);
                 //return;
                string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);//20022775_m.jpg
                int i = filename.LastIndexOf(".");
    string extendname=filename.Substring(i, filename.Length - i);
    if (!(extendname == ".jpg"))
    {
     
     Response.Write("图片格式错误，必须为.jpg格式的图片！");
     return;
    }//检查图片文件的格式
        
     if (FileUpload1.PostedFile.ContentLength == 0 || FileUpload1.PostedFile.ContentLength >= size)
             {
                 Response.Write("指定的文件大小不符合要求,大小必须小于300k!");
                 return;
             }//检查图片文件的大小

                Stream oStream = FileUpload1.PostedFile.InputStream;
             System.Drawing.Image oImage = System.Drawing.Image.FromStream(oStream);

             int owidth = oImage.Width; //原图宽度
                int oheight = oImage.Height; //原图高度

            if (owidth > LimitWidth || oheight > LimitHeight)
            {
                Response.Write("超过允许的图片尺寸范围,照片尺寸必须为120*160！");
                return ;
            }//检查是否超出规定尺寸
           

                string serverpath = Server.MapPath("~/app_uploads/                                                                ") + filename;//取得文件在服务器上保存的位置C:\Inetpub\wwwroot\WebSite1\images\20022775_m.jpg
                FileUpload1.PostedFile.SaveAs(serverpath);//将上传的文件另存为
                //this.Upload_info.Text = "上传成功！";
                Response.Write("上传成功！");
                insertPic(serverpath);//插入数据库
              
            }
        }
        catch (Exception ex)
        {
         Response.Write("上传发生错误！原因是：" + ex.ToString());
           // this.Upload_info.Text = "上传发生错误！原因是：" + ex.ToString();
        }

}

 

2.存入数据库

void insertPic(String path){
   FileStream fs=File.OpenRead(path);
   byte[] content=new byte[fs.Length];
   fs.Read(content,0,content.Length);
   fs.Close();
 
     SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["JaneConnection"].ConnectionString);    
        String sql = "insert into i_pic(pic) values(@pic)";
          SqlCommand comm=new SqlCommand(sql,con);
          con.Open();
        try {
        SqlParameter   para3=new   SqlParameter("@pic",SqlDbType.Image);
    para3.Value=content;
    comm.Parameters.Add(para3);

        int add=comm.ExecuteNonQuery();          
        if(add>0)
        {
         Response.Write("成功插入图片！");
        }

    
        } catch (Exception e){
           Response.Write(e.ToString());
        }
    }
  

 
3.从数据库中读取出来，用在页面上直接显示

void readPic(int _id){
   try
   {
         SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["JaneConnection"].ConnectionString);    
         String sql = "select pic from i_pic where id=@id";
          SqlCommand comm=new SqlCommand(sql,con);
         con.Open();
         SqlParameter   para4=new   SqlParameter("@id",SqlDbType.Int);
    para4.Value=_id;
    comm.Parameters.Add(para4);
    
    SqlDataReader reader=comm.ExecuteReader();
    while(reader.Read())
    {
     Response.BinaryWrite((byte[])reader["pic"]);
     //x_image=(byte[])reader["pic"];
    }
    reader.Close();
    con.Close();
         }
        catch(Exception e)
        {
         Response.Write(e.ToString());
        }
}

 

4.用Image控件显示：因为Image控件不能像byte[]直接显示图片，所以要倒一下，借用byte[]把它做成只显示图片的.aspx页，然后，在主页上放Image控件，控件的URL直接指向.aspx页就行了

<asp:Image ID=x_image Runat=server  ImageUrl="~/inner/pic.aspx/"/>