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This article mainly explains "how to import files into SQLServer2008 by ASP.NET". Interested friends may wish to have a look. The method introduced in this paper is simple, fast and practical. Let's let the editor take you to learn how ASP.NET imports files into SQLServer2008.

ASP.NET imports files into SQL Server mainly using the FileBytes property of the FileUpload control. This property returns a byte array from the file specified by the FileUpload control.

1. Database preparation in order to facilitate your understanding, here we only design two fields, one is the file type field, the field name is FileType, the other is to store the file content field, the field name is FileContent. Create a database named VarFile with the following statement: CREATE DATABASE VARFILE GO creates a table with the name FileInOut, and the statement is as follows: USE VARFILE GO CREATE TABLE FILEINTOU (FileType nvarchar (30) not null, FileContent varbinary (max) null)

two。 Add a control to run VS2008 and create a new website, add a FileUpload control to the page Default.aspx, ID is FileUpload1. Add three Button buttons at the same time, and the ID is fileUp and fileLoad. The Text property is set to upload File and download File, respectively.

3. Add code

(1) add namespaces because you are connected to the SQL Server database, so add using System.Data.Sqlclient and using System.Data namespaces. Also because you want to set the character set of the HTTP of the output stream to "gb2312" character encoding, add the using System.Text namespace. At the same time, because the exported file is strongly typed as a string, the using System.Collections.Specialized namespace is added.

(2) add the event code of the upload File button. When you click the upload File button, get the file type of the file selected by the FileUpload control and insert the byte array of the file into the database. Switch to Design view, double-click the "upload File" button, and add the event code of the "upload File" button as follows: copy the code as follows: protected void fileUp_Click (object sender,EventArgs e) {if (FileUpload1.FileName==string.Empty) {Response.Write ("altert ('Please select a file to upload'); return;} string mailto:connstr=@%22Data Source=69F638102711447\ SQL2008;Initial Catalog=VarFile;Integrated Security=Ture" / / Database connection string string theSelected = FileUpload1.FileName; / / get the suffix string extension=theSelected.Substring (theSelected.LastIndexOf (".")) .ToLower (); if (CheckFileType (extension)) / / if there is a specified file type {string contentType=GetContentType (extension); string sqlstr= "insert into FileInOut values (@ FileType,@FileCount)"; / / SQL statement string sqlstrclear= "truncate table FileInOut" for uploading files; / / empty database SQL statement SqlConnection con=new SqlConnection (connstr) / / instantiate the database connection object SqlCommand cmd=new SqlCommand (sqlstr,con); / / instantiate the upload file SQL command SqlCommand cmdclear=new SqlCommand (sqlstrclear,con); / / instantiate the database SQL command / / define the price type parameter cmd.Parameters.Add ("@ FileType", SlqDbType.NvarChar,30)) Cmd.Parameters ["@ FileType"] .value = contentType; / / define the file content parameter cmd.Parameters.Add (new SqlParameter ("@ FileCount", SqlDbType.NVarChar,30)); / / convert the file to a byte array as the value of @ FileCount cmd.Parameters ["@ FileCount"] .Value = FileUpload1.FileBytes; con.Open (); cmdclear.ExecuteNonQuery (); / execute the clean database command cmd.ExecuteNonQuery (); / / execute the file upload command}}

(3) add the function method to get the file type and the way to export the file. First, check whether the file type to be uploaded is within the specified price type. If so, you can import the file directly, and then obtain the file export method according to the file type and store it in the FileType field. The code is as follows: copy the code as follows: public static bool CheckFileType (string type) {StringDictionary sd=new StringDictionary (); / instantiate the collection StringDictionary class sd.Add (".doc", "application/msword") Sd.Add (".ppt", "application/vnd.ms-powerpoint"); sd.Add (".xsl", "application/vnd.ms-excel"); sd.Add (".rtf", "application/msword"); sd.Add (".html", "text/html"); sd.Add (".htm", "text/html"); sd.Add (".txt", "text/plain"); sd.Add (".pdf", "application/pdf"); return sd.ContainsKey (type) / / determine whether StringDictionary contains a specific key} public static string GetContentType (string extension) / / get output file mode {StringDictionary sd=new StringDictionary (); sd.Add (".doc", "application/msword"); sd.Add (".ppt", "application/vnd.ms-powerpoint"); sd.Add (".xsl", "application/vnd.ms-excel"); sd.Add (".rtf", "application/msword"); sd.Add (".html", "text/html") Sd.Add (".htm", "text/html"); sd.Add (".txt", "text/plain"); sd.Add (".pdf", "application/pdf"); return sd [extension]; / / returns the value of the corresponding key}

(4) upload a file, select a pdf file, click the "upload file" button, open the FileInOut table in the database, as shown in the figure.

At this point, I believe you have a deeper understanding of "how ASP.NET imports files to SQLServer2008". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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