Simple function to convert a CSV to a JS object/JSON.

csvToJSON.js

function csvToJSON(csv, textDelimiter = '"', fieldDelimiter = ",", logging = false) {

    //Split it by every character
    let f=csv.split("");

    //Track whether or not we're in a quote block right now
    let inQuote = -1;

    //Array to store all of the separated values
    let vals = [[]];

    //Temporary tracker for current field's string
    let currentString = "";

    //Track the array index for this line
    let index = 0;

    //Track the array index for what line we're on
    let lineIndex = 0;

    let lastChar = "";

    //Go through every character
    f.forEach((el)=>{

        //If we're at a line break and we're not in a quote
        if(el == "\n" && inQuote == -1) { 

            //Next index...
            index++;

            //And put the final string on the array for this line
            vals[lineIndex][index] = currentString;

            //Reset the string so it's squeaky clean for the next line
            currentString = "";

            //Take us out of a quote (shouldn't be in one anyway)
            inQuote = -1; 

            //To the next line!!!
            lineIndex++; 

            //Create an array at this line
            vals[lineIndex]=[]; 

            //Start at the beginning
            index=0; 
        }

        //A wild quotation mark appears! Take us out of quotes, captain. TODO add escape char support
        else if(el == textDelimiter && lastChar != "\\") { console.log(lastChar); inQuote *= -1; }

        //If we're not in a quote and we find a comma
        else if(inQuote==-1 && el == fieldDelimiter) { 

            //Set the value of the current index to the string we've been working on
            vals[lineIndex][index] = currentString; 

            //Reset our current string
            currentString = ""; 

            //Onto the next index!
            index++; 
        }

        //If it's just a plain old regular character, add it to the current string
        else if(inQuote) { currentString += el; }

        lastChar = el;
    });

    //We're at the end! Set the final string to the current string.
    vals[lineIndex][index+1] = currentString;

    //Say it out loud.
    console.log(vals);

    //Time to start working on the actual object, now that we have the array of lines. Izzy Wizzy let's get busy.

    //Put together a list of headers from the first line of the above
    let headers = [];
    for(let v = 0; v < vals[0].length; v++) {
        headers.push(vals[0][v])
    }
    if(logging) { console.log(headers); }

    //The object our JSON data will live in
    let obj = [];

    //Run through the values, starting at line 1
    for(let v = 1; v < vals.length; v++) {

        //Shorthand the current line
        let cval = vals[v];

        //The object to put this line's data into
        let cobj = {};

        //Throw a warning out if the number of items on this line doesn't match the number of headers--the data is bad or something went wrong above.
        if(cval.length != headers.length && logging) { console.warn("Number of values on line " + v + " does not match number of headers! I'll try my best!"); }

        //Go through each header
        for(let h = 0; h < headers.length; h++) {

            //And assign the value corresponding to its position on this line
            cobj[headers[h]] = cval[h];
        }

        //Add the current line's object to the master object array.
        obj.push(cobj);
    }

    //Here's what we came up with.
    if(logging) { console.log(obj); }

    //Throw the JSON back to the people.
    return JSON.stringify(obj);

}