xul/xpcom将图像从字符串复制到剪贴板

Question

我无法找到线索如何将图像复制到剪贴板。 我的代码如下所示：

var image = "data:image/png;base64,..." 

var io   = Components.classes["@mozilla.org/network/io-service;1"].getService(Components.interfaces.nsIIOService); 
var channel = io.newChannel(image, null, null); 
var input  = channel.open(); 

var trans = Components.classes["@mozilla.org/widget/transferable;1"].createInstance(Components.interfaces.nsITransferable); 
trans.addDataFlavor("image/png"); 
trans.setTransferData("image/png", input, input.available()); 

var clipid = Components.interfaces.nsIClipboard; 
var clip = Components.classes["@mozilla.org/widget/clipboard;1"].getService(clipid); 
clip.setData(trans, null, clipid.kGlobalClipboard); 

Answer 1

尼尔在新闻组已经指出，预期的图像数据是nsIContainer实例，而不是流。我找不到这样做，在网络上的任何例子，所以我修改了代码：

var image = "data:image/png;base64,..."; 

var io   = Components.classes["@mozilla.org/network/io-service;1"].getService(Components.interfaces.nsIIOService); 
var channel = io.newChannel(image, null, null); 
var input  = channel.open(); 
var imgTools = Components.classes["@mozilla.org/image/tools;1"].getService(Components.interfaces.imgITools); 

var container = {}; 
imgTools.decodeImageData(input, channel.contentType, container); 

var trans = Components.classes["@mozilla.org/widget/transferable;1"].createInstance(Components.interfaces.nsITransferable); 
trans.addDataFlavor("image/png"); 
trans.setTransferData("image/png", container.value, -1); 

var clipid = Components.interfaces.nsIClipboard; 
var clip = Components.classes["@mozilla.org/widget/clipboard;1"].getService(clipid); 
clip.setData(trans, null, clipid.kGlobalClipboard); 

对我来说这将映像复制到剪贴板正确。