Mám to napsáno takto:

var statusLabel = FormView1.FindControl("MeasGlobalStatusLabel") as Label;
switch(statusLabel.Text)
{
    case "Vyhovuje":
        statusLabel.ForeColor = System.Drawing.Color.Green;
        break;
    case "Nevyhovuje":
        statusLabel.ForeColor = System.Drawing.Color.Red;
        break;
}