divide by 0 error

[Matt]

Scenario:
A dataset exists with a number of columns in it. I want to add a new column
that will divide ColA by ColB.

How I've accomplished this is pretty simple, simply create an instance of
DataColumn, and set the .Expression property to ColA / ColB.

The problem is when I get to a row where ColB is 0, a divide by zero error
occurs. This seems like it should be something so common that it would be
heavily documented and such as to how to handle, but can't find anything.

 

[Kevin Yu [MSFT]]

Hi Matt,

First of all, I would like to confirm my understanding of your issue. From
your description, I understand that you have an Expression Column in a
DataTable whose value is a division from other 2 columns. When a column
value is 0, a Devide by 0 exception is thrown. If there is any
misunderstanding, please feel free to let me know.

Are you binding the whole DataSet to a DataGridView? If so, you can handle
the DataGridView.DataError to workaround this error dialogbox. Here is an
example.

private void dataGridView1_DataError(object sender,
DataGridViewDataErrorEventArgs e)
{
if (e.Exception is System.Data.EvaluateException)
//Do whatever you need.
}

If anything is unclear, please feel free to reply to the post.

Kevin Yu
Microsoft Online Community Support

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[Brendan Green]

..Expression = "IFF(ColB = 0, 0, ColA/ColB"

Will set the column to 0 if ColB is zero, otherwise does the division.

 

[msnews.microsoft.com]

You can if the expression to only run when it will not end up in divide by
zero.

You can calculate the aggregate on the data side with a conditional SQL
query.

If Binding
----------
You can set up the error event on the object you are binding and have it set
a specific value.

You can set up the the binding event to evaluate and determine what to put
into the grid.

--
Gregory A. Beamer
MVP; MCP: +I, SE, SD, DBA

*************************************************
Think Outside the Box!
*************************************************

 

[Matt]

that took care of the problem... still have a grid that I need to look at,
but other suggestions will probably help there.

Thanks