Using PapaParse, I’m able to parse out a relatively large CSV file quickly into a JS Array..of Objects. My biggest issue with the way PapaParse returns the data is that it doesn’t allow me to choose the first field as the object key, so I’ve been learning the .filter function (though I was worried that iterating over an array of objects in JS would be slow especially with a dataset that large).  The takeaway here is that I can run a custom function on each ELEMENT of the array (and pass the anonymous function a temporary reference named however I like).  In this case my function looks like this:

 var newArray = workingResArray.filter(function(el){
 // el is a reference to each array ELEMENT that the filter is iterating through
 for (var i=0; i<searchArray.length; i++)
 {
 if (el['Long Name']==searchArray[i]){console.log("we found:",searchArray[i]);return el;}
 }
 }); // end of anonymous function inside of filter

This wasn’t immediately apparent for me and took a little bit of tinkering (It’s been a while!).  Inside these functions I searched for the relevant key data and in my latest iteration I load all the relevant data from the export (now 200k rows and about 18mb).  A search of 20 unique entries takes about 80ms total to compile the relevant data and write it out to a CSV for one of our plugins, cool!

Another small project for work in which the department requests to take a weekly export of data in the form of a CSV, or more accurately a list of semi-colon separated values (ssv?) and append certain data depending on the year found within each row.

Another fun quick project written using javascript/jQuery that utilizes the FileReader() class in jQuery and the onchange event in javascript on the <input type=”file”> element to load that file into a new instance of FileReader object and begin an asynchronous process that loads the lines into an array. From there the array is copied over and the relevant keywords/data are appended to the end of each array element according to predefined criteria.

This code is executed and creates the new payload client-side.

Script Here