Use the legend.position property to determine the position of the legend. The "Auto" position places the legend to the right or below the chart depending on the control size:

Legend Position:

// This file locates: "Scripts/Lesson/C1FlexChart/LegendPosition.js".
c1.documentReady(function () {
    var theChart = wijmo.Control.getControl('#theChart');
    var legendPosition = wijmo.Control.getControl('#legendPosition ');
 
    legendPosition.textChanged.addHandler(function (s, e) {
        theChart.legend.position = s.text;
    });
});

using System.Web.Mvc;
 
namespace LearnMvcClient.Controllers
{
    public partial class C1FlexChartController : Controller
    {
        // GET: LegendPosition
        public ActionResult LegendPosition()
        {
            return View(Models.FlexChartData.GetSales1());
        }
    }
}

@using LearnMvcClient.Models
@model IEnumerable<FlexChartData.Sale>
 
@{
    var positions = new[] { "None", "Top", "Bottom", "Left", "Right", "Auto" };
}
 
<h1>
    @Html.Raw(Resources.C1FlexChart.LegendPosition_Title)
</h1>
 
<p>
    @Html.Raw(Resources.C1FlexChart.LegendPosition_Text1)
</p>
 
<div class="demo-settings">
    <label for="legendPosition">@Html.Raw(Resources.C1FlexChart.LegendPosition_Text2) </label>
    @Html.C1().ComboBox().Id("legendPosition").Bind(positions).Text("Right")
</div>
 
@(Html.C1().FlexChart<FlexChartData.Sale>().Id("theChart")
    .Bind("Country", Model)
    .Series(sb =>
    {
        sb.Add().Binding("Sales").Name("Sales");
        sb.Add().Binding("Expenses").Name("Expenses");
        sb.Add().Binding("Downloads").Name("Downloads");
    })
)