[UPLOAD mechanism explanation] FileUpload

zhaozj2021-02-16 52

When writing a website program, the section is written in the website, and there will be only the communication between the Client and Server, and there will be binary file transfer. How to transfer in HTML Form, it is necessary to comply with RFC 1867. .

Basically, post.jsp should have a similar HTML TAG below:

Input Your name:

Select the file:

This part is a category of HTML, interested in drilling RFC ...

Section 02 Multipart / Form-Data HTTP Performance Situation

When you press the transfer, Browser will send post's information to Server.

POST

Http: // localhost: 9000 / fileupload / upload.jsp HTTP / 1.1

Accept: image / gif, image / x-xbitmap, image / jpeg, image / pjpeg, application / vnd.ms-powerpoint, application / vnd.ms-excel, application / msword, * / *

Referr:

Http: // localhost: 9000 / fileupload / post.jsp

Accept-language: zh-tw, zh-cn; q = 0.7, en-us; q = 0.3

CONTENT-TYPART / FORM-DATA; Boundary = --------------------------- 7d33E580784

Accept-encoding: Gzip, deflate

User-agent: mozilla / 4.0 (compatible; msie 6.0; windows NT 5.0)

Host: www.softleader.com.tw

Content-Length: 3020

Connection: Keep-alive

Cache-Control: No-cache

Cookie: jsessionid = 3b31f07f56328e7b623a9ba1c4e3479d

We can know that contet-type is the transfer of Boundary with multipart / form-data.

Section 03 actual example

file upload </ title> <meta http-equiv = "content-type" content = "text / html; charSet = big5"> </ hEAD> <body bgcolor = "# ffffff" text = "# 000000"> Chapter 7 Archives Upload Example <form name = "form1" encTy = "multipart / form-data" method = "post" action = "jyfile.jsp"> Upload file 1: <input type = "file" name = "file1" size = "20" maxlength = "20"> Archive 1 Narrative: <input type = "text" name = "file1" size = "30" maxlength = "50"> Upload file 2: <input type = "file" name = "file2" size = "20" maxlength = "20"> Archive 2 Narration: <input type = "text" name = "file2" size = "30" maxlength = "50"> Upload Archive 3: <input type = "file" name = "file3" size = "20" maxlength = "20"> Archive 3 Narration: <input type = "text" name = "file3" size = "30" maxlength = "50"> <input type = "submit" value = "Upload"> <input type = "reset" value = "Clear"> </ form> </ body> </ html> This picture only shows part, please click View Full Picture = 514) WINDOW.OPEN (this.SRC); Else Return False; "HSPACE = 2 SRC =" http: //hi1-pass-ren/log/uploadimg/fileupload-1.gif "οnlοad =" ing (this. Width> = 514) {this.style.cursor = 'Hand'; this.alt = '!!! This image only shows part, please click View Full Picture !!!'; this.previoussibling.Style.Display = '' ;} "vspace = 2 border = 0> Section 04 Transfer format Post /neWSpaper/JYFILE.JSP HTTP / 1.1 Accept: image / gif, image / x-xbitmap, image / jpeg, image / pjpeg, application / vnd.ms-powerpoint, application / vnd.ms-excel, application / msword, * / * Referr: Http: // localhost: 9000 / newspaper / jyfile.html Accept-language: zh-tw, zh-cn; q = 0.7, en-us; q = 0.3 CONTENT-TYPART / FORM-DATA; Boundary = --------------------------- 7D31091C6205FC Accept-encoding: Gzip, deflate User-agent: mozilla / 4.0 (compatible; msie 6.0; windows NT 5.0) Host: Localhost: 9000 Content-Length: 428583 Connection: Keep-alive Cache-Control: No-cache Cookie: jsessionid = E141744815A8FF44F8AA9BA6D5946710 ---------------------------- 7D31091C6205FC Content-disposition: form-data; name = "file1"; filename = "c: / test / test .exe" Content-Type: Application / OcTet-stream XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX (binary garbled) ---------------------------- 7D31091C6205FC Content-disposition: form-data; name = "file1" EXE ---------------------------- 7D31091C6205FC Content-disposition: form-data; name = "file2"; filename = "c: / test / test .gif" Content-Type: Image / GIF XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX (binary garbled) ---------------------------- 7D31091C6205FC Content-disposition: form-data; Name = "file2" GIF ---------------------------- 7D31091C6205FC Content-disposition: form-data; name = "file3"; filename = "c: / test / test.xls" Content-Type: Application / VND.MS-Excel XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX (binary garbled) ---------------------------- 7D31091C6205FC Content-disposition: form-data; name = "file3" XLS ----------------------------- 7D31091C6205FC - Section 05 to jyfile.jsp <% @ Page ContentType = "text / html; charset = big5" language = "java"%> <% @ page import = "java.io. *"%> <% @ Page Import = "java.util. *"%> <% @ Page import = "org.apache.commons.fileUpload. *"%> <% // Declare the file to place the file to the server / .... / upload directory String savedirectory = "c: //"; / / Declaration Temporary Directory String tmpdirectory = "c: //"; // Declaration to the total size of the files, the unit is BYTE, -1 means unlimited INT MAXPOSTSIZE = 1024 * 1024; %> <% // Declare a variable in which the store is described String FileDescription = NULL; // Declare a variable in the store name String filename = NULL; // Declare the variables of the stored upload file size Long filesis = 0; // Declare the variables of the stored upload file String contentType = NULL; / / Calculate the number of uploaded files INT count = 0; %> <% DiskfileUpload Upload (); // Set the size of the memory store, exceed the write file, have a set temporary directory, the temporary file is placed in the temporary directory Upload.setsizethreshold (4096); / / Set the total upload size limit Upload.setsizemax; // Set the temporary directory Upload.setRepositoryPath (TMPDIRECTORY); List / * fileItem * / items = UPLOAD.PARSEREQUEST (REQUEST); %> <body> <% Iterator it = items.iterator (); INT TMP = 0; FileItem TmpInm = NULL; While (item.hasnext ()) { TMP ; FILEITEM ITEM = (FileItem) iter.next (); IF (item.isformfield ()) { // If it is a general field, get a file narrative FileDescription = item.getstring (); } Else { / / Otherwise get a file information FILENAME = item.getname (); // Because different browsers will pass Path FileName, some only FileName Try { // for Wintel Platform FILENAME = filename.substring (filename.lastindexof ("//") 1); // for UNIX-LIKE Platform FileName = filename.substring (filename.lastindexof ("/") 1); } Catch (exception ex) { Out.println (ex); } Contenttype = item.getContentType (); filesis = item.getsize (); TmpItem = Item; } // Because a file is two fields, each read two fields are handled once IF (TMP == 2 && FileSize! = 0) { COUNT ; %> You uploaded by <% = count%> profile: The file name is: <% = filename%> The size of the file is: <% = filesize%> Bytes Archive type: <% = contenttype%> Description file: <% = FileDescription%> <% // write the archive into the archive directory Try { Out.println (filename); FILE UPLOADEDFILE = New File (SaveDirectory FileName); TmpItem.write (UPLOADEDFILE); } Catch (exception ex) { Out.println (ex); } TMP = 0; } Else if (tmp == 2 && filesis == 0) { TMP = 0; } // end if } // End while %> You have uploaded <% = count%> file </ body> </ html> This picture only shows part, please click View Full Picture = 514) WINDOW.OPEN (THIS.SRC); Else Return False; "HSPACE = 2 SRC =" http: //hi1-pass-ren/log/uploadimg/fileupload-2.gif "οnlοad =" if (this. Width> = 514) {this.style.cursor = 'Hand'; this.alt = '!!! This image only shows part, please click View Full Picture !!!'; this.previoussibling.Style.Display = '' ;} "vspace = 2 border = 0> Section 06 Struts fileupload Why do Struts 1.1 should I wait for Commons-FileUpload 1.0? Because Struts has a Subpackage called org.apache.struts.upload. *; This is the setting-related File format If you use struts for MVC Framework, you can refer to the development of Struts-Upload.war in Example. (1) Establish UPLOAD.JSP <html: form action = "Upload.do?queryparam=su" ENCTYPE = "Multipart / Form-Data"> File description: <html: text property = "theText" /> select the file: <html: file property = "theFile" /> </ html: form> (2) Establish uplineform.java Public class uploadform extends actionform { ........ Public string getthetext () { Return Thet; } Public void setthetxt (string thetext) { THIS.THETEXT = Thet; } Public Formfile getthefile () { Return thefile; } Public void setthefile (formfile thefile) { THIS.THEFILE = Thefile; } ........ } Note that formfile is built in org.apache.struts.upload in package (3) Write uploadAction Public ActionForward Execute (ActionMapping Mapping, Actionform Form, HTTPSERVLETREQUEST REQUEST, HttpservletResponse response) { UPLOADFORM Theform = (UPLOADFORM) Form; String text = theform.getthetext (); Formfile file = theform.getthefile (); String filename = file.getfilename (); String contenttype = file.getContentType (); String size = (file.getfilesize () "bytes"); .... // See how you handle .... // You can use InputStream to get file.getinputstream, etc. Return mapping.findforward ("thepageyouwannago"); } (4) Establish struts-config.xml <form-beneans> <form-bean name = "Uploadform" TYPE = "org.apache.struts.Webapp.upload.uploadform" /> </ form-beans> <action-mappings> <! - UPLOAD ACTION -> <action path = "/ upload" type = "org.apache.struts.Webapp.upload.uploadaction" Name = "UploadForm" Scope = "Request" Input = "/ Upload.jsp"> <forward name = "display" path = "/ display.jsp" /> </ action> For details, please download Struts 1.1 SRC Review Content Section 06 Summary</div><div class="text-center mt-3 text-grey"> 转载请注明原文地址:https://www.9cbs.com/read-18863.html</div><div class="plugin d-flex justify-content-center mt-3"></div><hr><div class="row"><div class="col-lg-12 text-muted mt-2"><h2 class="h6 mb-0 small"><a class="text-secondary" href="tag-2.html">9cbs</a></h2></div></div></div></div><div class="card card-postlist border-white shadow"><div class="card-body"><div class="card-title"><div class="d-flex justify-content-between"><div>New Post(0) </div><div></div></div></div><ul class="postlist list-unstyled"> </ul></div></div><div class="d-none threadlist"><input type="checkbox" name="modtid" value="18863" checked /></div></div></div></div></div><footer class="text-muted small bg-dark py-4 mt-3" id="footer"><div class="container"><div class="row"><div class="col">CopyRight © 2020 All Rights Reserved </div><div class="col text-right">Processed: 0.047, SQL: 9</div></div></div></footer><script src="./lang/en-us/lang.js?2.2.0"></script><script src="view/js/jquery.min.js?2.2.0"></script><script src="view/js/popper.min.js?2.2.0"></script><script src="view/js/bootstrap.min.js?2.2.0"></script><script src="view/js/xiuno.js?2.2.0"></script><script src="view/js/bootstrap-plugin.js?2.2.0"></script><script src="view/js/async.min.js?2.2.0"></script><script src="view/js/form.js?2.2.0"></script><script> var debug = DEBUG = 0; var url_rewrite_on = 1; var url_path = './'; var forumarr = {"1":"Tech"}; var fid = 1; var uid = 0; var gid = 0; xn.options.water_image_url = 'view/img/water-small.png'; </script><script src="view/js/wellcms.js?2.2.0"></script><a class="scroll-to-top rounded" href="javascript:void(0);"></a><a class="scroll-to-bottom rounded" href="javascript:void(0);" style="display: inline;"></a></body></html><script> var forum_url = 'list-1.html'; var safe_token = 'keMsRwQRvW4bgniMTzOLwnJpjSgq0ZlDh_2FydpbxaFlFZ1a1PBNM_2FmNkdklC5m7itoyj4gkwrnGFdUQ7b2gXG8Q_3D_3D'; var body = $('body'); body.on('submit', '#form', function() { var jthis = $(this); var jsubmit = jthis.find('#submit'); jthis.reset(); jsubmit.button('loading'); var postdata = jthis.serializeObject(); $.xpost(jthis.attr('action'), postdata, function(code, message) { if(code == 0) { location.reload(); } else { $.alert(message); jsubmit.button('reset'); } }); return false; }); function resize_image() { var jmessagelist = $('div.message'); var first_width = jmessagelist.width(); jmessagelist.each(function() { var jdiv = $(this); var maxwidth = jdiv.attr('isfirst') ? 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