如何根据DatagGridView中绑定列的值计算未绑定列值？(How to calculate unbound column value based on value of bound colum

如何根据DatagGridView中绑定列的值计算未绑定列值？(How to calculate unbound column value based on value of bound colum in DatagGridView?)

我的DataGridView中有几列，其中一列是未绑定列，DataGridVIew位于VirtualMode中。

当调用CellValueNeeded事件时，我想基于Cells[2]的值计算Cells[0]的值，该值位于有限列中，位于底层DataSource 。

这就是我尝试这样做的方式：

private void dgvItems_CellValueNeeded(object sender, DataGridViewCellValueEventArgs e) { e.Value = dgvItems.CurrentRow.Cells[2].Value * 5; //simplified example }

但是，我收到System.StackOverflowException因为它dgvItems.CurrentRow.Cells[2].Value调用dgvItems.CurrentRow.Cells[2].Value导致调用另一个CellValueNeeded事件。 等等......然而，Cells [2]不是一个未绑定的列，所以在常识上它不应该导致递归调用，除非获取任何列（绑定或未绑定）的值来激活该事件...

我不能在这里使用SQL Expression，我不能在任何SQL调用中预先计算e.Value。 在实例中，Cell [2] .Value是HashTable中使用的一个键，它将返回Cells [0]（e.Value）的正确值。

我能做什么？

I have few columns in my DataGridView, one of them is an unbound column and the DataGridVIew is in VirtualMode.

When CellValueNeeded event is called, I want to calculate value of Cells[0] basing on the value of Cells[2] which is in bounded column to the underlaying DataSource.

This is how I try to do this:

private void dgvItems_CellValueNeeded(object sender, DataGridViewCellValueEventArgs e) { e.Value = dgvItems.CurrentRow.Cells[2].Value * 5; //simplified example }

However, I am getting System.StackOverflowException because it seams that call to dgvItems.CurrentRow.Cells[2].Value results in call to another CellValueNeeded event. And so on and so on... However Cells[2] is not an unbound column, so on common sense it should not result in recursive call unless getting value of any column(bound or unbound) firest that event...

I can not use here SQL Expression and I can not precalculate e.Value in any SQL call. In real example Cells[2].Value is a key used in HashTable which will return a correct value for the Cells[0] (e.Value).

What can I do?

最满意答案

您需要有选择性并仅对第0列采取行动：

//untested private void dgvItems_CellValueNeeded(object sender, DataGridViewCellValueEventArgs e) { if (e.Column == 0) { e.Value = dgvItems.CurrentRow.Cells[2].Value * 5; //simplified example } }

You need to be selective and act on column 0 only:

//untested private void dgvItems_CellValueNeeded(object sender, DataGridViewCellValueEventArgs e) { if (e.Column == 0) { e.Value = dgvItems.CurrentRow.Cells[2].Value * 5; //simplified example } }