Create UploadLargeFile.js

Author: Suvabrataroy

UploadLargeFile.js

@@ -0,0 +1,72 @@
+/* Author : Suvabrata Roy
+   Email  : [email protected] */
+
+function UploadLargeFile(file, callback, PostURL) {
+    var fileSize = file.size;
+    var chunkSize = 1 * 1024 * 1024; // bytes
+    var offset = 0;
+    var BOF = 0;
+    var self = this; // reference purpose
+    var FileReadInBlocks = null;
+
+    var readEventHandler = function(evt) {
+        if (evt.target.error == null) {
+            offset += evt.target.result.length;
+            callback(evt.target.result, BOF, function() {
+                if (offset >= fileSize) {
+                    console.log("Done reading file");
+                    //console.log(new Date());
+                    return;
+                }
+                FileReadInBlocks(offset, chunkSize, file)
+            }, PostURL);
+
+            BOF = offset;
+        } else {
+            console.log("Read error: " + evt.target.error);
+            return;
+        }
+
+        if (offset >= fileSize) {
+            console.log("Done reading file");
+            //console.log(new Date());
+            return;
+        }
+    }
+
+    FileReadInBlocks = function(_offset, length, _file) {
+        var r = new FileReader();
+        var blob = _file.slice(_offset, length + _offset);
+        console.log(_offset);
+        r.onload = readEventHandler;
+        r.readAsDataURL(blob);
+    }
+    // now let's start the read with the first block
+    FileReadInBlocks(offset, chunkSize, file);
+}
+
+
+function AsyncUpload(data, fileposition, seekNext, PostURL) {
+    var xhttp = new XMLHttpRequest();
+    xhttp.onreadystatechange = function() {
+        if (this.readyState == 4 && this.status == 200) {
+            seekNext();
+        }
+    };
+
+    xhttp.open("POST", PostURL, true);
+    xhttp.setRequestHeader("Content-type", "application/json; charset=utf-8");
+    xhttp.send(JSON.stringify({
+        Data: data,
+        OffSet: fileposition
+    }));
+
+}
+
+
+//Usage 
+/*
+function UploadFileOnSubmit() {
+    var file = document.getElementById("FileInput").files[0]
+    UploadLargeFile(file, AsyncUpload, "URL To Post The data");
+} */