javascript - 以代码格式下载图像

我试图制作一个下载图像的按钮，而我所做的是，做了一个像这样的功能：

function download_image(){
    $file = $_POST['file'];
    header('Content-Description: File Transfer');
    header("Content-type: application/octet-stream");//notice this content-type, it will force a download since browsers think that's what they should do with .exe files
    header("Content-disposition: attachment; filename= ".$file."");
    readfile($file);
}

当点击下载按钮时，我执行了这个js：

$.ajax({
        type:"POST",
        url:'..address to../download_image',
        data:{
            file:imgElem
        },
        success:function(){
            alert('image downloaded');
        }
    });

现在的问题是我没有图像名称，但是编码的图像是这样的：

<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAABBgAAAEtCAYAAACibtPQAAAgAElEQVR4nO3dX28c150mYH+c+S57s5d7uVcFGMEGuQiwgW+ycCEAsdl4gQjGJqsyYIyCYEbwEDXKZD1KNLHVtjMZDeM/kmmWLJmOrSiOzViOJDJiHNtnLoLqLRarm8VDFfsU63mBBzabzWZ12/rp1MtTzSdCCKEoipBlWciyLFRVFbpSVdX8PlmWhTzPO+8nIiIiIiIiItPLE7PZLJRlGUIIoSzLUBRF5x3rgkFEREREREREpJ0nmh8oGEREREREREQkJvOCIc/z+U6GrrQvkVh2XxERERERERGZVo61g6H+nN0MIiIiIiIiItLME+0b+hYHy94QUkRERERERESmlSfKsgyz2SyEEMJsNjvw2yHyPO/c0WAHg4iIiIiIiIg080QIi39NZbNgaL8HQ11KiIiIiIiIiIgcukRCREREREREROS4UTCIiIiI...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">

所以问题是我应该如何下载图像？？？请帮忙：（

最佳答案

只需将window.location设置为编码的URI，例如

window.location.href = 'data:image/png;base64,iVBORw0KGgo...

或者您也可以打开一个弹出窗口

http://jsfiddle.net/vaibviad/VE8Qn

如果您想拥有文件名和扩展名，那么也可以尝试一下

<a download="FILENAME.EXT" href="data:image/png;base64,asdasd...">Download</a>

下面的链接是演示文件，其下载属性带有文件名和扩展名

http://jsfiddle.net/vaibviad/VE8Qn/3/

注意：Download attribute不被广泛支持

关于javascript - 以代码格式下载图像，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/19175070/