Question

当我更改单元格值以进行更新时抛出InvalidOperationException并直接单击菜单条项以打开新的Winform。

   private void dgv_category_CellValueChanged(object sender, DataGridViewCellEventArgs e)
        {
            DataTable dt = new DataTable();
            dt = u.operationOnDataBase(sqlquery_selectCategory, 3);
            if (dt.Rows.Count > 0)
            {
                MessageBox.Show("Category Already Exist...");

            }
            else
            {
                u.operationOnDataBase(sqlquery_UpdateCategory, 1);
                u.SyncMaster("update", "CategoryDetails", 0, Convert.ToInt32(dgv_category[1, e.RowIndex].Value.ToString()));//---------Sync
            }

            try
            {
                dgv_category.DataSource = null; //here Throwing exception

                u.operationOnDataBase(sqlquery, 3);
                dgv_category.DataSource = u.dt;


            }
            catch (InvalidOperationException)
            {
                // exception
            }
        }

异常 - 操作无效，因为它导致a   可重入调用SetCurrentCellAddressCore函数。

在System.Windows.Forms.DataGridView.SetCurrentCellAddressCore（Int32   columnIndex，Int32 rowIndex，Boolean setAnchorCellAddress，Boolean   validateCurrentCell，Boolean throughMouseClick）at   System.Windows.Forms.DataGridView.set_CurrentCell（的DataGridViewCell   System.Windows.Forms.DataGridView.set_DataSource（Object。）   值）

Answer 1

不是直接设置DataSource，而是将DataSource设置为BindingSource，然后更改BindingSource.DataSource？

例如

//create bindingSource in the WinForms Designer

则...

try
{
   dgv_category.DataSource = null;
   dgv_category.Rows.Clear();
}
catch{}
bindingSource.DataSource = ut.dt;
dgv_category.DataSource = bindingSource;
bindingSource.ResetBindings(true);

Answer 2

尝试这个

private void dgv_category_CellValueChanged(object sender, DataGridViewCellEventArgs e)
    {
        DataTable dt = new DataTable();
        dt = u.operationOnDataBase(sqlquery_selectCategory, 3);
        if (dt.Rows.Count > 0)
        {
            MessageBox.Show("Category Already Exist...");

        }
        else
        {
            u.operationOnDataBase(sqlquery_UpdateCategory, 1);
            u.SyncMaster("update", "CategoryDetails", 0, Convert.ToInt32(dgv_category[1, e.RowIndex].Value.ToString()));//---------Sync
        }

        try
        {
           /// dgv_category.DataSource = null; //you don't need to set it to null just remove it

            //try set empty data table 
            DataTable dt = new DataTable();
           dgv_category.DataSource = dt;

            u.operationOnDataBase(sqlquery, 3);
            dgv_category.DataSource = u.dt;


        }
        catch (InvalidOperationException)
        {
            // exception
        }
    }

数据网格视图CellValueChanged事件抛出InvalidOperationException

2 个答案: