https://www.renfrewshiregolfunion.co.uk/shared/js/knockout.file-binding.js?$WCREV$

1/*
2 * File input binding for knockout.js
3 * Jesse Kipp - Nov 14, 2013
4 *
5 * A special binding for file input elements. Think of it like 'value', but
6 * storing the encoded data from a FileReader object.
7 *
8 * Usage 1:
9 * <input type='file' data-bind='file: fileInput'>
10 * If fileInput is an observable, it will be assigned the value of the base64
11 * encoded file data.
12 *
13 * Usage 2:
14 * <input type='file' data-bind='file: {data: fileInput, name: fileName}'>
15 * When passing an object, use the following keys
16 *   data: the observable to store the file data (required)
17 *   name: the observable to store the file name
18 *   allowed: permitted content types (text/javascript, etc), as a string or
19 *     array of strings. All other types will be ignored.
20 *   prohibited: content types that will always be ignored.
21 *   reader: an existing FileReader object. If not defined, creates a new
22 *     one internally.
23 */
24 
25(function () {
26  var factory = function (ko) {
27
28    ko.bindingHandlers['file'] = {
29      init: function(element, valueAccessor, allBindings) {
30        var fileContents, fileName, allowed, prohibited, reader;
31    
32        if ((typeof valueAccessor()) === "function") {
33          fileContents = valueAccessor();
34        } else {
35          fileContents = valueAccessor()['data'];
36          fileName = valueAccessor()['name'];
37    
38          allowed = valueAccessor()['allowed'];
39          if ((typeof allowed) === 'string') {
40            allowed = [allowed];
41          }
42    
43          prohibited = valueAccessor()['prohibited'];
44          if ((typeof prohibited) === 'string') {
45            prohibited = [prohibited];
46          }
47    
48          reader = (valueAccessor()['reader']);
49        }
50    
51        reader || (reader = new FileReader());
52        reader.onloadend = function() {
53          fileContents(reader.result);
54        }
55    
56        var handler = function() {
57          var file = element.files[0];
58    
59          // Opening the file picker then canceling will trigger a 'change'
60          // event without actually picking a file.
61          if (file === undefined) {
62            fileContents(null)
63            return;
64          }
65    
66          if (allowed) {
67            if (!allowed.some(function(type) { return type === file.type })) {
68              console.log("File "+file.name+" is not an allowed type, ignoring.")
69              fileContents(null)
70              return;
71            }
72          }
73    
74          if (prohibited) {
75            if (prohibited.some(function(type) { return type === file.type })) {
76              console.log("File "+file.name+" is a prohibited type, ignoring.")
77              fileContents(null)
78              return;
79            }
80          }
81    
82          reader.readAsDataURL(file); // A callback (above) will set fileContents
83          if (typeof fileName === "function") {
84            fileName(file.name)
85          }
86        }
87    
88        ko.utils.registerEventHandler(element, 'change', handler);
89      }
90    }
91  }
92  
93  if ((typeof define === 'function') && define.amd) {
94    define(['knockout'], factory);
95  } else {
96    factory(ko);
97  }
98})();