more functions

index.js

@@ -67,6 +67,12 @@ function base64StringToBlob(base64, type) {
   });
 }
 
+function binaryStringToBlob(binary, type) {
+  return Promise.resolve().then(function () {
+    return base64StringToBlob(btoa(binary), type);
+  });
+}
+
 function blobToBase64String(blob) {
   return blobToBinaryString(blob).then(function (binary) {
     return btoa(binary);
@@ -147,8 +153,16 @@ function imgSrcToBlob(src, type) {
   });
 }
 
-function plainTextToBlob(text) {
+function arrayBufferToBlob(buffer, type) {
-  return createBlob([text], 'text/plain');
+  return Promise.resolve().then(function () {
+    return createBlob([buffer], type);
+  });
+}
+
+function blobToArrayBuffer(blob) {
+  return blobToBinaryString(blob).then(function (binary) {
+    return binaryStringToArrayBuffer(binary);
+  });
 }
 
 module.exports = {
@@ -160,5 +174,8 @@ module.exports = {
   dataURLToBlob      : dataURLToBlob,
   blobToBase64String : blobToBase64String,
   base64StringToBlob : base64StringToBlob,
-  plainTextToBlob    : plainTextToBlob
+  binaryStringToBlob : binaryStringToBlob,
+  blobToBinaryString : blobToBinaryString,
+  arrayBufferToBlob  : arrayBufferToBlob,
+  blobToArrayBuffer  : blobToArrayBuffer
 };

test/test.js

@@ -13,13 +13,20 @@ tests();
 
 function tests() {
 
+  var transparent1x1Png =
+    'iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR4nGP6zwAAAgcBApocMXEA' +
+      'AAAASUVORK5CYII=';
+  var black1x1Png =
+    'iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAAAAAA6fptVAAAACklEQVR4nGNiAAAABgADNjd8qAAA' +
+      'AABJRU5ErkJggg==';
+
   beforeEach(function () {
   });
   afterEach(function () {
   });
   describe('basic tests', function () {
     it('convert plain blobs', function () {
-      var blob = blobUtil.plainTextToBlob('foo');
+      var blob = blobUtil.createBlob(['foo'], 'text/plain');
       blob.type.should.equal('text/plain');
       return blobUtil.blobToBase64String(blob).then(function (base64) {
         base64.should.equal('Zm9v');
@@ -63,13 +70,6 @@ function tests() {
       });
     });
 
-    var transparent1x1Png =
-      'iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR4nGP6zwAAAgcBApocMXEA' +
-        'AAAASUVORK5CYII=';
-    var black1x1Png =
-      'iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAAAAAA6fptVAAAACklEQVR4nGNiAAAABgADNjd8qAAA' +
-        'AABJRU5ErkJggg==';
-
     it('convert base64 to png', function () {
       return blobUtil.base64StringToBlob(transparent1x1Png, 'image/png').then(function (blob) {
         return blobUtil.blobToBase64String(blob);
@@ -116,5 +116,43 @@ function tests() {
       });
     });
 
+    it('convert to binary and back', function () {
+      var binary = atob(transparent1x1Png);
+      return blobUtil.binaryStringToBlob(binary, 'image/png').then(function (blob) {
+        blob.size.should.equal(68);
+        return blobUtil.blobToBase64String(blob).then(function (base64) {
+          base64.should.equal(transparent1x1Png);
+          return blobUtil.blobToBinaryString(blob);
+        }).then(function (bin) {
+          bin.should.equal(atob(transparent1x1Png));
+        });
+      });
+    });
+
+    it('convert to array buffer and back', function () {
+      var bin = atob(transparent1x1Png);
+      var buffer = new ArrayBuffer(bin.length);
+      var arr = new Uint8Array(buffer);
+      for (var i = 0; i < bin.length; i++) {
+        arr[i] = bin.charCodeAt(i);
+      }
+      return blobUtil.arrayBufferToBlob(buffer, 'image/png').then(function (blob) {
+        blob.size.should.equal(68);
+        return blobUtil.blobToBase64String(blob).then(function (base64) {
+          base64.should.equal(transparent1x1Png);
+          return blobUtil.blobToBinaryString(blob);
+        }).then(function (bin) {
+          bin.should.equal(atob(transparent1x1Png));
+          return blobUtil.blobToArrayBuffer(blob);
+        }).then(function (buff) {
+          buff.byteLength.should.equal(68);
+          return blobUtil.arrayBufferToBlob(buff, 'image/png');
+        }).then(function (blob) {
+          return blobUtil.blobToBase64String(blob);
+        }).then(function (base64) {
+          base64.should.equal(transparent1x1Png);
+        });
+      });
+    });
   });
 }