Construct and pass JavaScript string list to ASP.NET MVC Controller action (not using ajax)

Question

How do I construct a list of strings in JavaScript and pass it to window.location such that it will show up as List<string> on the C# side of the fence?
(Not using Ajax POST, but instead using window.location)

Example ASP.NET MVC Controller action:

public FileResult GetMyCsvFile(List<string> columnNames)
{
  ...
}

Example JavaScript:

$('export-button').click(function (e) {
    e.preventDefault();

    // TODO: How do I construct the next line(s) such that it can pass a list of strings to my C# controller action?
    window.location = ROOT_PATH + "Home/GetMyCsvFile ... ????
});

Answer 1

Try

"Home/GetMyCsvFile?columnNames=firstColumn&columnNames=secondColumn...."

As an example, create the <a> tag and give it an id

 @Html.ActionLink("Click me", "Test", "Task", null, new { id = "myLink" })

then in the script (note I've used jquery since that's what you used in the question)

$('#myLink').click(function (e) {
  e.preventDefault();
  // Define the values to pass to the controller
  var firstCol = 'value1';
  var secondCol = 'value2';
  // Construct url with query string
  var path = $(this).attr('href');
  path += '?columnNames=' + firstCol + '&columnNames=' + secondCol;
  // Navigate to the view
  window.location = path;
});

If its a variable list of values, you would need to construct the url in a loop, something like

for (var i = 0; i < myValues.length; i++) {
  if (i === 0) {
    path += '?columnNames=' + myValues[i];
  } else {
    path += '&columnNames=' + myValues[i];
  }
}