C # Picture Processing

<%@ Page Debug = "true" language= "C #"%>
<%@ Import namespace= "System.IO"%>
<%@ Import namespace= "System.Data"%>
<%@ Import namespace= "system.web"%>
<%@ Import namespace= "System.Data.SqlClient"%>
<!--This procedure is developed by Peng Yong of Changsha Railway Public Security Department, all rights reserved, and shall not be reproduced-->
<script language= "C #" runat= "Server" >

Page load Events
public void Page_Load (Object Sender,system.eventargs e)
{

Define picture Flags
String Pys_pic;
Pys_pic= "";

Define folder names
String Pys_dir;
Pys_dir=datetime.now.year.tostring ();

Define the previous part of the file name to prevent the upload file from being overwritten by file name duplication
String Pys_filename;

If the client has uploaded the file, save the
if (! IsPostBack)
{
liuxi.text= "Waiting to upload";
}
Else
{
Check for article IDs, if not, process
if (request["Pysid"]==null | request["Pysid"]== "")
{
strstatus.text= "<font color=red> error occurred, you did not enter the page from the proper way, please close this page!" </font> ";
}
Else
{
Traversing file Form elements
System.Web.HttpFileCollection Files=system.web.httpcontext.current.request.files;
Status information
System.Text.StringBuilder strmsg=new System.Text.StringBuilder ("<font color=red> uploaded file information for:</font> &LT;HR size=1 color=blue> ");
int filecount;
int Filecount=files. Count;
Store the client address of the uploaded image to detect the size of the uploaded image
String Imgpath;
Check whether the upload file is a picture
String Pys_type;
Save picture to generate thumbnail width
int pys_width;
Try
{
Database connection string
String connectionstring= "server= (local);d atabase=csc;uid=forcool;pwd=";

String Sql= "select * from Upfile";


Creating SqlConnection objects
SqlConnection thisconnection=new SqlConnection (ConnectionString);
Creates a Dataadaper object and initializes it.
SqlDataAdapter Adapter=new SqlDataAdapter (Sql,thisconnection);




Creating a DataSet Object
DataSet data=new DataSet ();


Create a SqlCommandBuilder object and associate it with SqlDataAdapter
SqlCommandBuilder builder=new SqlCommandBuilder (adapter);


Adapter. Fill (data, "upfile");


For (Filecount=0;filecount<files. count;filecount++)
{
Define the number of access client uploaded files
System.Web.HttpPostedFile Postedfile=files[filecount];
String filename,fileextension;
Get the file name of the upload
Filename=system.io.path.getfilename (Postedfile.filename);
if (filename!=string.empty)
{
Get file name extension
Fileextension=system.io.path.getextension (FileName);
Uploaded file information
Strmsg.append ("<font color=red><b>" + (filecount+1) + ".</b></font>");
Strmsg.append ("uploaded file type:" +postedfile.contenttype.tostring () + "<br>");
Strmsg.append ("Client file Address:" +postedfile.filename+ "<br>");
Strmsg.append ("The filename of the uploaded file:" +filename+ "<br>");
Strmsg.append ("Upload file extension:" +fileextension+ "<br>");
Strmsg.append ("Upload file Size:" +postedfile.contentlength+ "<br>");


Name the file at the current time (accurate to milliseconds) without the Chinese name and avoid coding errors that cannot be downloaded or displayed
Pys_filename=datetime.now.year.tostring () +datetime.now.month.tostring () +datetime.now.day.tostring () + DateTime.Now.Hour.ToString () +datetime.now.minute.tostring () +datetime.now.second.tostring () + DateTime.Now.Millisecond.ToString ();

Create a random Number object
Random rnd=new Random ();
Call next method to generate random number
Pys_filename+=rnd. Next (1,100000). ToString ();

pys_filename+= "-";
Pys_filename+=filecount;
pys_filename=request.querystring["Pysid"]+ "-" +pys_filename;

Pys_type=fileextension;
Pys_type=pys_type. ToLower ();

Assign an initial value to the thumbnail width
pys_width=0;
If it's a picture, check the size, and if the picture is too large, create thumbnails.
if (pys_type== ". jpg" |   pys_type== ". gif" |   pys_type== ". bmp" | pys_type== ". png")
{
Pys_pic= "yes";
Get the path to the uploaded picture
Imgpath=postedfile.filename;
Create an Image object for a selected picture
System.Drawing.Image Image=system.drawing.image.fromfile (Imgpath);
Get the height and width of a picture using the height and width properties of the Image object
Strmsg.append ("Upload picture height:" +image.) Height.tostring () + "<br>");
Strmsg.append ("Upload picture width:" +image.) Width.tostring () + "<br>");
If the uploaded image is over 100KB,

if (postedfile.contentlength>100000 | | Image. width>400)
{
Generate thumbnails
System.Drawing.Image.GetThumbnailImageAbort Callb=null;
Pys_width= (image. Height) *200/(image. Width);
System.Drawing.Image Newimage=image. Getthumbnailimage (200,pys_width,callb,new system.intptr ());
Save thumbnails
NewImage. Save (Server.MapPath ("" +pys_dir+ "\\small-") +pys_filename+fileextension);
Freeing resources occupied by NewImage objects

Compression Processing of graphics
Pys_width= (image. Height) *400/(image. Width);
Newimage=image. Getthumbnailimage (400,pys_width,callb,new system.intptr ());
Save a compressed diagram
NewImage. Save (Server.MapPath ("" +pys_dir+ "\") +pys_filename+fileextension);
Freeing resources occupied by NewImage objects
NewImage. Dispose ();
Strmsg.append ("The uploaded picture is larger than 100KB, and a thumbnail has been generated for this figure in order not to affect the browsing speed of the dial-up Internet unit." <br> ");
}
Release the resources occupied by image
Image. Dispose ();
}


Strmsg.append ("

Add uploaded file information to the dataset
DataRow Newrow=data. tables["Upfile"]. NewRow ();
newrow["Pysid"]=request["Pysid"];
newrow["file name"]=filename;
newrow["file type"]=fileextension;
newrow["File Size"]=postedfile.contentlength;
newrow["File location"]=pys_dir+ "/" +pys_filename+fileextension;
if (pys_width>0)
{
newrow["thumbnail position"]=pys_dir+ "/small-" +pys_filename+fileextension;
}
Data. tables["Upfile"]. Rows.Add (NewRow);