tx.js

function getTableFromController(cols, rows) {

    var serviceURL = "/Home/GetTableFromController";

    $.ajax({
        type: "POST",
        url: serviceURL,
        contentType: 'application/json',
        data: JSON.stringify({
            Columns: cols,
            Rows: rows
        }),
        success: successFunc,
        error: errorFunc
    });

    function successFunc(data, status) {
        TXTextControl.loadSelection(TXTextControl.streamType.InternalUnicodeFormat, data);
    }

    function errorFunc() {
        alert('Error');
    }
}