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javascripthtmlarrayscsvpapaparse

Serverside CSV file converting it into an JavaScript array


I'm working on a project where I need to be able to update an HTML table, and I would do it through javascript. I have not yet made an HTML site for this project, for I would try to convert a CSV file to a Java array, which would update the HTML table.

I have been trying with papa parse, but it would not work for me. I have no experience with npm and installing and getting stuff to work like Papa parsa. I have found this website, which has a great function to convert CSV to an array. One problem with this function is, that I can't take a local file on the server, and put it into the function as I do with a string. Maybe I have overlooked something?

  • I have got Papa Parse to work somehow, but I can't figure out how I use it on a local file, so I have two codes for the job, but I don't know how to get them to do it or how good the outcome is.

  • I just got a random CSV file as a test file. Normal.csv came from papa parse website.

-- to sum up -- I want to take a CSV file, turn it into a Java array, and then make that into an HTML table

Here is my long HTML file, with all scripts - no CSS at this point.

File(s) is being hosted on local Apache/XAMPP server.

<head>
    <title>Test af Papa Parse</title>
</head>
<body>
    <p>Hey - Test paraghaph</p>
    <script src="node_modules/papaparse/papaparse.min.js"></script> 
    <script src="node_modules/jquery/dist/jquery.min.js"></script> 
/*edit: src="http://localhost/test/node_modules/papaparse/papaparse.min.js"*/
/*edit: src="http://localhost/test/node_modules/jquery/dist/jquery.min.js"*/
    <script>    

      var config = {
        download: true,
        // rest of config ...
        delimiter: "",  // auto-detect
        newline: "",  // auto-detect
        quoteChar: '"',
        escapeChar: '"',
        header: false,
        trimHeaders: false,
        dynamicTyping: false,
        preview: 0,
        encoding: "",
        worker: false,
        comments: false,
        step: undefined,
        complete: undefined,
        error: undefined,
        download: false,
        skipEmptyLines: false,
        chunk: undefined,
        fastMode: undefined,
        beforeFirstChunk: undefined,
        withCredentials: undefined,
        transform: undefined
      }

      var data = csv2array("http://localhost/test/normal.csv")

      var data2 = Papa.parse("http://localhost/test/normal.csv", config)
      console.log("papa parsa - direktly: "+ Papa.parse("http://localhost/test/normal.csv", config))
      console.log(data)
      console.log("data2 = "+data2)
      console.log(data2);

      /**
      * Convert data in CSV (comma separated value) format to a javascript array.
       *
       * Values are separated by a comma, or by a custom one character delimeter.
       * Rows are separated by a new-line character.
       *
       * Leading and trailing spaces and tabs are ignored.
       * Values may optionally be enclosed by double quotes.
       * Values containing a special character (comma's, double-quotes, or new-lines)
       *   must be enclosed by double-quotes.
       * Embedded double-quotes must be represented by a pair of consecutive 
       * double-quotes.
       *
       * Example usage:
       *   var csv = '"x", "y", "z"\n12.3, 2.3, 8.7\n4.5, 1.2, -5.6\n';
       *   var array = csv2array(csv);
       *  
       * Author: Jos de Jong, 2010
       * 
       * @param {string} data      The data in CSV format.
       * @param {string} delimeter [optional] a custom delimeter. Comma ',' by default
       *                           The Delimeter must be a single character.
       * @return {Array} array     A two dimensional array containing the data
       * @throw {String} error     The method throws an error when there is an
       *                           error in the provided data.
       */ 
      function csv2array(data, delimeter) {
        // Retrieve the delimeter
        if (delimeter == undefined) 
          delimeter = ',';
        if (delimeter && delimeter.length > 1)
          delimeter = ',';

        // initialize variables
        var newline = '\n';
        var eof = '';
        var i = 0;
        var c = data.charAt(i);
        var row = 0;
        var col = 0;
        var array = new Array();

        while (c != eof) {
          // skip whitespaces
          while (c == ' ' || c == '\t' || c == '\r') {
            c = data.charAt(++i); // read next char
          }
          // get value
          var value = "";
          if (c == '\"') {
            // value enclosed by double-quotes
            c = data.charAt(++i);

            do {
              if (c != '\"') {
                // read a regular character and go to the next character
                value += c;
                c = data.charAt(++i);
              }
              if (c == '\"') {
                // check for escaped double-quote
                var cnext = data.charAt(i+1);
                if (cnext == '\"') {
                  // this is an escaped double-quote. 
                  // Add a double-quote to the value, and move two characters ahead.
                  value += '\"';
                  i += 2;
                  c = data.charAt(i);
                }
              }
            }
            while (c != eof && c != '\"');
            if (c == eof) {
              throw "Unexpected end of data, double-quote expected";
            }

            c = data.charAt(++i);
          }
          else {
            // value without quotes
            while (c != eof && c != delimeter && c!= newline && c != ' ' && c != '\t' && c != '\r') {
              value += c;
              c = data.charAt(++i);
            }
          }

          // add the value to the array
          if (array.length <= row) 
            array.push(new Array());
          array[row].push(value);
          // skip whitespaces
          while (c == ' ' || c == '\t' || c == '\r') {
            c = data.charAt(++i);
          }

          // go to the next row or column
          if (c == delimeter) {
            // to the next column
            col++;
          }
          else if (c == newline) {
            // to the next row
            col = 0;
            row++;
          }
          else if (c != eof) {
            // unexpected character
            throw "Delimiter expected after character " + i;
          }
          // go to the next character
          c = data.charAt(++i);
        }  
        return array;
      }
    </script>
</body>

Solution

  • I think your best option is to simplify everything until you figure out exactly what you need. Here is a very basic working Papa.parse. You have no need for the config file unless you are doing something that specifically requires it. Here is a plnkr link

    <html>
    
      <head>
        <script data-require="[email protected]" data-semver="3.1.1" src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
        <link rel="stylesheet" href="style.css" />
        <script src="https://cdnjs.cloudflare.com/ajax/libs/PapaParse/4.6.1/papaparse.min.js"></script>
      </head>
    
      <body>
        <script>
          let csvString = '2018-06-29,2018-06-29,111211,15:35:00,77,15:50:00,,Blah,Internet User,,Baln bla,0,4,0,0,0,$516.00 ,$120.00 ,$396.00 ,$19.80 ,$415.80 ,,$0.00 ,$0.00 ,$415.80';
          //let array = Papa.parse(csvString);
          //console.log(array);
         let array = Papa.parse('http://localhost/test/filename.csv',{download:true});
         console.log(array);
    
        </script>
      </body>
    
    </html>
    

    Once you have this working on your local server, delete the csvString, load the file in and go from there... edit: npm is a great tool for a lot of things, however from what I can tell, this doesn't seem like a great use case for it.