为什么Line会头尾相连

这是数据

string sqlS1 = "select numX,numY from BrokenLine10";
DataTable dt1 = Sqlhelper.GetTable(sqlS1);
for (int i = 0; i < dt1.Rows.Count; i++)
{
    this.chart1.Series[0].Points.AddXY(i+1, dt1.Rows[i][1]);
}

你折线类型选错了吧