Create dataTable column definition from uploaded csv data

Question

M trying to create datatable out of uploaded csv file. the only problem i'm facing is defining table column header. Currently i have done it like this, defining header manually.

var table = $('#example').DataTable({
    columns: [{
          "title": "Number",
          "data": "Number"
      }, {
          "title": "Category",
          "data": "Category"
      }, {
          "title": "Assignment group",
          "data": "Assignment group"
      }
      ]

});

and passing csv data through Jquery CSV

 var f = event.target.files[0];
if (f) {
    var r = new FileReader();
    r.onload = function(e) {
        console.log("on load function");
        var result = $.csv.toArrays(e.target.result);
        table.rows.add($.csv.toObjects(e.target.result)).draw();
    }
    r.readAsText(f);
} else {
    alert("Failed to load file");
}

this is working fine. I want to define the column header directly from csv file itself.

Tried

 var f = event.target.files[0];
if (f) {
    var r = new FileReader();
    r.onload = function(e) {
        console.log("on load function");
        var result = $.csv.toArrays(e.target.result); // This will give CSV rows
        var csvHeader = result[0]; // This will give first CSV header
        var option;
        $.each( csvHeader, function( value ){
           console.log(value)
           // Now iterate each value to define Datatable column
           option = // Define column  which will create below column definition 

           /* columns: [{
                         "title": "Number",
                         "data": "Number"
                     }, {
                         "title": "Category",
                         "data": "Category"
                     }, {
                         "title": "Assignment group",
                         "data": "Assignment group"
                     }, {
                          "title": "Short description",
                          "data": "Short description"
                      },
                      {
                          "title": "Description",
                          "data": "Description"
                      }
                     ]*/


        });


        var table = $('#example').DataTable({

          //Define datatable passing column definition as option 
        });



        table.rows.add($.csv.toObjects(e.target.result)).draw();
    }
    r.readAsText(f);
} else {
    alert("Failed to load file");
}

Thanks in advance.

Answer 1

Any reason for using FileReader instead of $.get or similar? FileReader is not supported by all browsers, like IE9 and Opera mini.

Anyway - since you read a CSV file, and end up with arrays of strings ready to be added to the table, there is no need for defining data properties in columns. In fact it only takes a few very simple steps to generate a dataTable showing a CSV using $.csv. The below code takes any well formed CSV and publish it as a dataTable :

$.get(<CSV FILE>, function(csv) {
    var data = $.csv.toArrays(csv),
        columns = [];

    //create the columns object
    data[0].forEach(function(col) {
        columns.push({ title: col });
    })

    //remove the CSV header row for convenience 
    data.splice(0,1);

    //create the dataTable
    var table = $('#example').DataTable({
        columns: columns
    })

    //insert rows
    data.forEach(function(row) {
        table.row.add(row).draw();
    })

})