Javascript 多个XMLHttpRequest.send或eventlisteners内存泄漏？

我目前正在实现文件的上传。因为我需要处理大量文件，所以我开始对文件进行切片，并将其分为1mb块发送，只要文件

\u offset+=length
是一个或多或少明显的错误为什么
xhr
是一个全局变量？我很确定你不是有意的。@Bergi
\u offset+=length
是一个复制粘贴错误，最好是一段旧代码，但谢谢你告诉我。xhr只是试图找到我的漏洞，并使代码保持最新（我想，全局与否对我的漏洞没有影响），但将其编辑回了局部变量。这里也有同样的问题。可能与？@gpalomar有关。我已经更改了代码，并发送了与WebWorkers同步的块，因此整个上传都只有一个对象，即使图形不再显示泄漏，问题仍然是一样的。然而，我能够在IE上重现类似的错误。
var sliceCount = 0;
var sendCount = 0;
var fileID = generateUUID();
var maxChunks = 0;
var userNotified = false;

function parseFile(file)
{
    var fileSize = file.size;
    var chunkSize = 1024 * 1024;//64 * 1024; // bytes
    var offset = 0;
    var self = this; // we need a reference to the current object
    var chunkReaderBlock = null;
    var numberOfChunks = fileSize / chunkSize;
    maxChunks = Math.ceil(numberOfChunks);

    // gets called if chunk is read into memory
    var readEventHandler = function (evt)
    {
        if (evt.target.error == null) {
            offset += evt.target.result.byteLength;

            sendChunkAsBinary(evt.target.result);
        }
        else
        {
            console.log("Read error: " + evt.target.error);
            return;
        }

        if (offset >= fileSize) {
            console.log("Done reading file");
            return;
        }

        // of to the next chunk
        chunkReaderBlock(offset, chunkSize, file);
    }

    chunkReaderBlock = function (_offset, length, _file)
    {
        var r = new FileReader();
        var blob = _file.slice(_offset, length + _offset);

        sliceCount++;
        console.log("Slicecount: " + sliceCount);

        r.onload = readEventHandler;
        r.readAsArrayBuffer(blob);

        blob = null;
        r = null;
    }
    // now let's start the read with the first block
    chunkReaderBlock(offset, chunkSize, file);
}

function sendChunkAsBinary(chunk)
{
    var progressbar = $("#progressbar"), bar = progressbar.find('.uk-progress-bar');
    // create XHR instance
    var xhr = new XMLHttpRequest();

    // send the file through POST
    xhr.open("POST", 'upload.php', true);

    var progressHandler = function (e)
    {
        // get percentage of how much of the current file has been sent
        var position = e.loaded || e.position;
        var total = e.total || e.totalSize;
        var percentage = Math.round((sendCount / maxChunks) * 100);

        // set bar width to keep track of progress
        bar.css("width", percentage + "%").text(percentage + "%");
    }
    // let's track upload progress
    var eventSource = xhr.upload || xhr;
    eventSource.addEventListener("progress", progressHandler);

    // state change observer - we need to know when and if the file was successfully uploaded
    xhr.onreadystatechange = function ()
    {
        if (xhr.readyState == 4)
        {
            if (xhr.status == 200)
            {
                eventSource.removeEventListener("progress", progressHandler);
                if (sendCount == maxChunks && !userNotified)
                {
                    userNotified = true;
                    notifyUserSuccess("Datei hochgeladen!");
                    setTimeout(function ()
                    {
                        progressbar.addClass("uk-invisible");
                        bar.css("width", "0%").text("0%");
                    }, 250);

                    updateDocList();
                }
            }
            else 
            {
                notifyUser("Fehler beim hochladen der Datei!");
            }
        }
    };

    var blob;
    if (typeof window.Blob == "function") {
        blob = new Blob([chunk]);

    } else {
        var bb = new (window.MozBlobBuilder || window.WebKitBlobBuilder || window.BlobBuilder)();
        bb.append(chunk);
        blob = bb.getBlob();
    }
    sendCount++;
    var formData = new FormData();
    formData.append("chunkNumber", sendCount);
    formData.append("maxChunks", maxChunks);
    formData.append("fileID", fileID);
    formData.append("chunkpart", blob);

    xhr.send(formData);
    progressbar.removeClass("uk-invisible");
    console.log("Sendcount: " + sendCount);
}