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FireFox browser uses Javascript to upload large files_PHP tutorial

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2016-07-13 10:25:46833browse

This program uses the feature of Firefox 3.x browser to read local files, realizes the function of uploading large files through xmlHttPRequest, and dynamically displays the upload progress during the upload process. With slight modifications and cooperation with the server, many functions such as breakpoint resume transmission can be realized.
This example mainly studies some features of FireFox's file-input node. Other client applications, such as Flash, Silverlight, etc., when implementing client-side large file uploads, are different from this one in terms of data transmission and server-side storage. The ideas in the examples are basically the same.
Note: There seems to be a critical point in file size, but what this critical point is has not yet been confirmed. It is recommended not to use this method to upload files exceeding 100M.
The following is the client javascript code

Copy the code The code is as follows:

/*
* FireFoxFileSender version 0.0.0.1
* by MK winnie_mk(a)126.com
*
* [This program is limited to FireFox3.x version, other browsers Whether the server can run has not been tested. 】
* 【Test passed: FireFox 3.6.8 / Apache/2.2.11 (Win32) php/5.2.6 】
* ****************** *************************************************** **********
* This program takes advantage of the feature of the 3.x FireFox browser that can read local files
* Implements the function of uploading large files through xmlhttpRequest
* And can Dynamically display the upload progress during the upload process
* With slight modifications and cooperation with the server, many functions such as breakpoint resumption can be realized
* This example is mainly to study some features of FireFox's file-input node
* Other client applications, such as Flash, Silverlight, etc., when implementing client-side large file uploads
* In terms of data transmission and server-side storage, the idea is basically the same as this example
* Note: file size There seems to be a tipping point, but what that tipping point is has not yet been confirmed. It is recommended not to use this method to upload files exceeding 100M.
************************************************* ************************************
*/
function FireFoxFileSender(config){
var conf = config || {};
/*
* Error message queue
*/
this.errMsg = [];
/*
* Determine whether all parameters are complete
*/
this.f = typeof conf.file == 'string' ?
document.getElementById(conf.file) : conf.file;
if(!this.f){ this. errMsg.push('Error: Not set the input file.'); }
else if(this.f.files.length < 1){ this.errMsg.push('Error: Not select a file.' ); }
else {
this.fileName = this.f.value;
/*
* Failed when trying to send the binary stream directly, sending base64 encoded data instead.
*/
this.data = (this.data = this.f.files[0].getAsDataURL())
.substr(this.data.indexOf(',') + 1);
this.length = this.data.length;
/*
* Actual file size
*/
this.fileSize = this.f.files[0].fileSize;
         /*
                                                                                                                                                        🎜> */
this.url = conf.url;
if(!this.url){
this.errMsg.push('Error: Not set the instance url to send binary.');
 }
/*
* The size of the sent data packet. Default 100kb
*/
this.packageSize = conf.packageSize || 102400;
/*
* The size of each data packet sent should be a multiple of 4 to ensure that the server-side conversion to base64 encoding is correct.
*/
if(this.packageSize % 4 != 0)
this.packageSize = parseInt(this.packageSize / 4) * 4;

this.onSendFinished = conf.onSendFinished || null;
this.onSending = conf.onSending || null;
this.onError = conf.onError || null;
}
FireFoxFileSender.prototype = {
/*
* Record the currently sent data
*/
currentData: null,
/*
* Record the reading position
*/
position: 0,
/*
* Data size. The value is the length of the base64 string.
*/
length: -1,
/*
* Check the error queue and try to trigger the onError event
*/
checkError: function(){
if(this .errMsg.length > 0){
                                                                                                         ;
return;
}
},
/*
* Create XMLHttpRequest
*/
createSender: function(){
var xhr = new XMLH ttpRequest();
       xhr.open('POST', this.url, true); Then read and send in a loop.
                                                                                                                                                                         */
                                                                                     onSending == 'function') _.onSending(_, xhr);
                                                                       var send = setTimeout( function(){
_.send();
clearTimeout(send);
send = null;
}, 100);                                                                          
},
/*
* Send data
*/
send: function(){
this.checkError();
/*
* Get the current Data to be sent
*/
this.currentData = this.data.substr(this.position, this.packageSize);
/*
* Change postion, simulate data flow shift
 */
if(this.currentData.length > 0) {
var xhr = this.createSender();
/*
* Custom header information to notify the server of file-related information
* This part can be modified for actual application.
             */
            xhr.setRequestHeader('#FILE_NAME#', this.fileName);
            xhr.setRequestHeader('#FILE_SIZE#', this.length);
            xhr.setRequestHeader('#CONTENT_TYPE#', this.contentType);

            xhr.send(this.currentData);
        } else if(typeof this.onSendFinished == 'function') {
            /*
             * 触发onSendFinished事件
             */
            this.onSendFinished(this);
        }
    },
    /*
     * 计算已发送数据百分比
     */
    percent : function(){
        if(this.length <= 0 ) return -1;
return Math.round((this.position / this.length) * 10000) / 100;
},
onSendFinished : null, //该事件是以本地数据发送完成为触发,并不是服务器端返回的完成信息。
onSending : null,
onError : null
}

/*
* Upload button event
*/
function send(fileID){
var sender = new FireFoxFileSender(
) /*
* Upload configuration file
*/
                                                                                                                           /*< ​​​​​Change according to server specific conditions. IIS6 defaults to 200K
* /
PackageSize: '200000',
/ *
*Trigger the event when an error occurs. Error in the sending process.
🎜> Delete sender;
                                                                                  ){
var per = sd.percent();
                  document.getElementById('Message').
triggered by onreadystatechange event * If there are no other errors during the transmission process, it can basically be determined that the server-side reception is completed
'); }
              ,
           /*
                                                                  
                                                                                                                                       
* Just make sure xhr returns readyState == 4 and status == 200
* The sending will continue
* How the server returns the completion information can be customized by changing the code of the receiving data page
* Then make a judgment based on the value of xhr.responseText }
);
sender.send();
}


The following is the server-side php code



Copy code

The code is as follows:

/* * Get input information */$b64 = file_get_contents("php://input");/*
* Get header information
*/
$headers = getallheaders();
$fileName = $headers['#FILE_NAME#'];
$contentType = $headers['#CONTENT_TYPE# '];

/*
* Make some judgments and processing...
*/

/*
* The following is a simple response from the server to sending data

* - If data is posted, output the length of the binary stream after converting base64 to a binary stream

* - Otherwise Output 0
* This is just an example, and this information is not received on the js side
* Similarly, you can also use methods such as writing feedback information in the header

* Feedback information to the client

* The main purpose is to determine whether there are other problems during the upload process
* To ensure that the uploaded file is complete
*/
if(!empty($b64)){
$stream = base64_decode($ b64);
echo strlen($stream);
/*
* Write the file in append mode
* Modify the file save location here
*/
$file = fopen( '' . $fileName , 'a');
if($file)
if(fwrite($file, $stream))
fclose($file);
} else echo '0 ';


Complete client code



Copy code

The code is as follows:


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5 FireFoxFileSender - !! ONLY FOR FireFox !!
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