动态生成图片列 设置好了 ImageLayout = DataGridViewImageCellLayout.Stretch 自动适应
但是在加载数据图片后 图片还是平铺显示 
请问要如何才能 真正的自动适应
生成列代码:
  
/// <summary>
        /// 返回一个定义了DataGridViewColumn的名字和数据绑定字段的数组
        /// 用于DataGridView的列显示
        /// </summary>
        /// <param name="columnNameArray">列名字的数组</param>
        /// <param name="specialColumnIndex">需要特殊设置的列宽的列的索引和宽度</param>
        /// <returns>定义好的DataGridViewColumn对象数组</returns>
        public static DataGridViewColumn[] SetDgViewColumnProperty(string[] columnNameArray,
                                                                   System.Collections.Hashtable specialColumnIndex,
                                                                    int i_img)
        {            //然后获得数组的边界,定义返回的DataGridViewColumn的数组范围            int arrCount = columnNameArray.Length;
            //定义返回的DataGridViewColumn
            var resultColumn = new DataGridViewColumn[arrCount];
            //设置一个是否需要进行特殊列宽度设置的标志            bool SpecialWidthFlag = specialColumnIndex != null;
            //bool SpecialWidthFlag = specialColumnIndex.Equals(null)?false:true;
            //循环数组
            for (int i = 0; i < columnNameArray.Length; i++)
            {
                if (i_img == i)
                {
                    var tmpColumn_IMG = new DataGridViewImageColumn
                    {
                        DataPropertyName = columnNameArray[i].Trim().ToUpper(),
                        Name = columnNameArray[i].Trim().ToUpper(),
                        ImageLayout = DataGridViewImageCellLayout.Stretch,                        
                    };
                    //设置列对应的数据绑定的名字                    resultColumn[i] = tmpColumn_IMG;
                }
                else
                {
                    var tmpColumn = new DataGridViewTextBoxColumn
                    {
                        DataPropertyName = columnNameArray[i].Trim().ToUpper(),
                        Name = columnNameArray[i].Trim().ToUpper()
                    };
                    //设置列对应的数据绑定的名字                    //设置列的名字
                    if (SpecialWidthFlag)//如果需要特殊设置
                    {
                        if (specialColumnIndex.ContainsKey(i))//如果是特殊需要设置的列,设置为自定义的宽度
                        {
                            tmpColumn.Width = (int)specialColumnIndex[i];
                            if ((int)specialColumnIndex[i] == 0)//如果此列的宽度为0,说明不显示
                                tmpColumn.Visible = false;
                        }
                    }
                    else
                        tmpColumn.Width = 80;//其余的采用普通宽度
                    resultColumn[i] = tmpColumn;
                }
            }
            //返回结果
            return resultColumn;
        }