如何在Java脚本中将PDF文件转换为base64字符串

Question

I have created an app in sencha touch cordova, and in my app I have a functionality to download PDFs.

I have successfully downloaded a pdf file, but now I want to convert the PDF into a base64 string using JavaScript.

Can anybody tell me how to do it?

Answer 1

See if your JavaScript environment has the " atob " and " btoa " functions available:

var encodedData = window.btoa("Hello, world"); // encode a string
var decodedData = window.atob(encodedData); // decode the string

These convert a string to and from Base64 encoding.

Answer 2

Trying using the logic below.

 <input id="inputFile" type="file" onchange="convertToBase64();" />

function convertToBase64(){
    //Read File
    var selectedFile = document.getElementById("inputFile").files;
    //Check File is not Empty
    if (selectedFile.length > 0) {
        // Select the very first file from list
        var fileToLoad = selectedFile[0];
        // FileReader function for read the file.
        var fileReader = new FileReader();
        var base64;
        // Onload of file read the file content
        fileReader.onload = function(fileLoadedEvent) {
            base64 = fileLoadedEvent.target.result;
            // Print data in console
            console.log(base64);
        };
        // Convert data to base64
        fileReader.readAsDataURL(fileToLoad);
    }
}

Note : This snippet was taken from stackoverflow, but I dont remember the link :(