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POCannot use "map" function within async module
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copied!<p>I am using node.js "async" module and need to use the "map" method.<br> Basically I have an array that contains other arrays. The inner arrays contains 2 elements, a type and an image filename. </p> <pre><code>var arr0 = []; var arr1 = ["type1", "image1.jpg"]; jsonArr.push(obj1); var arr2 = ["type2", "image2.jpg"]; jsonArr.push(obj2); </code></pre> <p>For each inner array, I want to get the base64 encoding of the image identified by the filename and add this encoding string as the third element of the array.</p> <p>I'm doing something like this: </p> <pre><code>var fs = require("fs"); var async = require("async"); function getImageEncoding(arr, callback){ console.log("getEncoding:" + arr + "\n"); // Get image filename image = arr[1]; // Read file and get base64 encoding fs.readFile(image, function(err, original_data){ var base64Image = original_data.toString('base64'); console.log("test:" + base64Image + "\n"); // Modify current arr by appendingthe base64 encoding of the image callback(null, arr.push(base64Image)); }); } async.map(arr0, getImageEncoding, function(err, results){ console.log("in async.map: " + results + "\n"); }); </code></pre> <p>I know the arr.push(base64Image) stuff is the thing that is not correct, but I cannot figure out how to return the modified element. </p> <p>In map(arr, iterator, callback) documentation, it is specified: </p> <p>"The iterator is called with an item from the array and a callback for when it has finished processing." </p> <p>The thing is I cannot figure out how to feed the callback with the new arrays.</p>

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