javascript 在javascript中转换base64字符串中的图像？
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Converting the image in base64 string in javascript?
提问by M Sach
i have html form with ENCTYPE="multipart/form-data" .It just contains the textbox of type 'file' which browses the file from local box.Here is the textbox code snippet
我有一个带有 ENCTYPE="multipart/form-data" 的 html 表单。它只包含从本地框中浏览文件的“文件”类型的文本框。这是文本框代码片段
<td>
<input name="fileNameAttr" id="filePath" size="52" type="file" value="">
</td>
I browse the file some image file from local box. The moment i select the file, filePath gets populated in text box. Now on click of some button, i want to convert the image in to base64 String in javascript. I am not using HTML5. Can i achieve it in javascript?
我从本地框中浏览了一些图像文件。我选择文件的那一刻，filePath 将填充在文本框中。现在单击某个按钮，我想将图像转换为 javascript 中的 base64 字符串。我没有使用 HTML5。我可以在 javascript 中实现它吗？
i can see some solution on net using HTML5 but that does not solve my purpose. If i need to use some third party utility , i can do that.
我可以在网上看到一些使用 HTML5 的解决方案，但这并不能解决我的目的。如果我需要使用某些第三方实用程序，我可以这样做。
EDIT:-looks like jquery can help with $.base64.encode( "this is a test" ); but how to use it with type="file"?
编辑：-看起来 jquery 可以帮助 $.base64.encode( "this is a test" ); 但是如何将它与 type="file" 一起使用？
回答by NullPoiиteя
this can be done by the HTML5 <canvas>for it
这可以通过HTML5来实现<canvas>它
or
或者
if you have node.js as an option then try something like that in img
如果你有 node.js 作为选项，那么在 img 中尝试类似的东西
or <img src="data:image/png;base64,jkasfhsdjkhsadf" />
或者 <img src="data:image/png;base64,jkasfhsdjkhsadf" />
example
例子
var fs = require('fs');
var base64_data = new Buffer(fs.readFileSync('sample.png')).toString('base64');
console.log('<img alt="sample" src="data:image/png;base64,' + base64_data + '">');
check this (also source of example)
检查这个（也是例子的来源）
Good read
好读
- How can you encode to Base64 using Javascript?//its for image
回答by Gung Foo
If you could access the local filesystem via javascript, what would keep you from reading the password file or other private data?
如果您可以通过 javascript 访问本地文件系统，什么会阻止您读取密码文件或其他私人数据？
This you can't do and it can't and won't be allowed in the future, for obvious reasons!
出于显而易见的原因，您不能这样做，将来也不能也不允许这样做！
