如果数据按字符串比较进行排序，那么因为当你填写它时你给了它字符串值。

不要 - 给它 double 值并使用Column DefaultCellStyle.Format属性格式化数据：如何：在Windows窗体DataGridView控件中格式化数据 [ ^ ]

If the data is being sorted by a string comparison, then that because when you filled it you gave it string values.
Don't - give it double values instead and use the Column DefaultCellStyle.Format property to format the data: How to: Format Data in the Windows Forms DataGridView Control[^]