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ReadFile in Nodejs Base64

J'essaie de lire une image côté client codée en base64. Comment lire avec nodejs?

Mon code:

// add to buffer base64 image
var encondedImage = new Buffer(image.name, 'base64');

fs.readFile(encondedImage, "base64", function(err, buffer){
    if ( err ) {
        console.log('In read file')
        console.log(err)
    } else {
        // check err
        lwip.open(buffer, 'jpg', function(err, image){
            console.log('in open')
            if ( err ) console.log(err)

            if ( image ) console.log(image)
            // check 'err'. use 'image'.
            // image.resize(...), etc.
        });
    }
})

Mais j'ai eu cette erreur:

In read file
[Error: Path must be a string without null bytes.]

* SOLUTION *

lwip accepte le tampon dans la méthode open.

// add to buffer base64 image from step
var encondedImage = new Buffer(image.name, 'base64');

// check err
lwip.open(encondedImage, 'jpg', function(err, image){
  // image.resize(..), etc
});
38
brunocascio

Je pense que l'exemple suivant montre ce dont vous avez besoin: http://www.hacksparrow.com/base64-encoding-decoding-in-node-js.html

L'essence de l'article est cette partie de code:

var fs = require('fs');

// function to encode file data to base64 encoded string
function base64_encode(file) {
    // read binary data
    var bitmap = fs.readFileSync(file);
    // convert binary data to base64 encoded string
    return new Buffer(bitmap).toString('base64');
}

// function to create file from base64 encoded string
function base64_decode(base64str, file) {
    // create buffer object from base64 encoded string, it is important to tell the constructor that the string is base64 encoded
    var bitmap = new Buffer(base64str, 'base64');
    // write buffer to file
    fs.writeFileSync(file, bitmap);
    console.log('******** File created from base64 encoded string ********');
}

// convert image to base64 encoded string
var base64str = base64_encode('kitten.jpg');
console.log(base64str);
// convert base64 string back to image 
base64_decode(base64str, 'copy.jpg');
84
Sjoerd

Dernière et meilleure façon de faire cela:

const fs = require('fs');
fs.readFileSync('/path/to/file.jpg', { encoding: 'base64' });
22
Mike Martin
var fs = require('fs');

function base64Encode(file) {
    var body = fs.readFileSync(file);
    return body.toString('base64');
}


var base64String = base64Encode('test.jpg');
console.log(base64String);