Write and read images (C # ASP. Net sqlserver)

Last Update:2018-12-05 Source: Internet

Author: User

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First, you must create a table that contains the image and type fields.

Webform1.aspx

<% @ Page Language = "C #" codebehind = "webform1.aspx. cs" autoeventwireup = "false" inherits = "readandwritepicfromdb. webform1" %> <! Doctype HTML public "-// W3C // dtd html 4.0 transitional // en"> <HTML>

Webform1.aspx. CS

Using system;
Using system. collections;
Using system. componentmodel;
Using system. Data;
Using system. drawing;
Using system. Web;
Using system. Web. sessionstate;
Using system. Web. UI;
Using system. Web. UI. webcontrols;
Using system. Web. UI. htmlcontrols;
Using system. IO;
Using system. Data. sqlclient;

Namespace readandwritepicfromdb
{
/// <Summary>
/// Summary of webform1.
/// </Summary>
Public class webform1: system. Web. UI. Page
{
Protected system. Web. UI. htmlcontrols. htmlinputfile file1;
Protected system. Web. UI. webcontrols. Button button1;
Private string filename = "";
Protected system. Web. UI. webcontrols. Button button2;
Private Static sqlconnection conn = NULL;

Private void page_load (Object sender, system. eventargs E)
{
// Place user code here to initialize the page
Connectdb ();
}

// Get the file name
Private string GetFile ()
{
Httppostedfile file = file1.postedfile;
Filename = file. filename;

Return filename;
}

// Read the file content
Private byte [] readfile ()
{
Filestream file = file. openread (GetFile ());
Byte [] content = new byte;
File. Read (content, 0, content. Length );
File. Close ();

Return content;
}

// Connect to the database
Private void connectdb ()
{
String connstr = "Initial catalog =; Data Source =; user id =; Password = ;";
Conn = new sqlconnection (connstr );
Conn. open ();
}

// Write the image to the database
Private void writeimage ()
{
Sqlcommand comm = conn. createcommand ();
Comm. commandtext = "insert into images (image, type) values (@ image, @ type )";
Comm. commandtype = commandtype. text;
Sqlparameter Param = comm. Parameters. Add ("@ image", sqldbtype. Image );
Param. value = readfile ();
Param = comm. Parameters. Add ("@ Type", sqldbtype. nvarchar );
Param. value = getcontenttype (New fileinfo (filename). extension. Remove (0, 1 ));

If (Comm. executenonquery () = 1)
Response. Write ("successful ");
Else
Response. Write ("fail ");

Conn. Close ();
}

// Get the suffix of the image
Private string getcontenttype (string extension)
{
String type = "";

If (extension. Equals ("jpg") | extension. Equals ("jpg "))
Type = "Jpeg ";
Else
Type = extension;

Return "image/" + type;
}

// Read images from the database
Private void ReadImage ()
{
Sqlcommand comm = conn. createcommand ();
Comm. commandtext = "select image, type from images ";
Comm. commandtype = commandtype. text;

Sqldatareader reader = comm. executereader ();
While (reader. Read ())
{
Response. contenttype = reader ["type"]. tostring (); // The read/write type must be set. Otherwise, the browser outputs the data as text.
Response. binarywrite (byte []) Reader ["image"]); // picture data
}

Response. Write ("successful ");
Response. End ();

Conn. Close ();
}
# Code generated by region web Form Designer
Override protected void oninit (eventargs E)
{
//
// Codegen: This call is required by the ASP. NET web form designer.
//
Initializecomponent ();
Base. oninit (E );
}

/// <Summary>
/// The designer supports the required methods-do not use the code editor to modify
/// Content of this method.
/// </Summary>
Private void initializecomponent ()
{
This. button1.click + = new system. eventhandler (this. button#click );
This. button2.click + = new system. eventhandler (this. button2_click );
This. Load + = new system. eventhandler (this. page_load );

}
# Endregion

Private void button#click (Object sender, system. eventargs E)
{
Writeimage ();
}

Private void button2_click (Object sender, system. eventargs E)
{
Try
{
ReadImage ();
}
Catch (exception EP)
{
Conn. Close ();
Response. End ();
}
}
}
}

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