DataGridView DataGridViewCheckBoxCell throws NullReferenceException

Karen Hill

I have a datagridview control on a form with a few of the columns being
DataGridViewCheckBox. Whenever I click on the checkbox to create a new
record I get a NullReference Exception thrown even though I check for
NULL using System.Convert.IsDbNull function.

What gives?

I'm catching the NullReferenceException, although I know it is not
correct to do for normal program flow. What is the solution?

Aug 30 '06 #1

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4858

Gino

Without seeing some code I can only generalize.

NullRefference errors indicate that a method or property is being accessed
without its class being instantiated.

DBnull errors indicate that a Null is being returned from the DataBase and
its type is not recognized by the compiler.

In that case you can look into overriding, and handle it inside.

"Karen Hill" <ka**********@yahoo.comwrote in message
news:11*********************@74g2000cwt.googlegrou ps.com...

>I have a datagridview control on a form with a few of the columns being
DataGridViewCheckBox. Whenever I click on the checkbox to create a new
record I get a NullReference Exception thrown even though I check for
NULL using System.Convert.IsDbNull function.

What gives?

I'm catching the NullReferenceException, although I know it is not
correct to do for normal program flow. What is the solution?

Aug 31 '06 #2

Rick Shaw

How about setting the threestate property if the checkbox to true. This
will allow the checkbox to accept anything other than true or false.

Try that out.

Rick..

"Karen Hill" <ka**********@yahoo.comwrote in message
news:11*********************@74g2000cwt.googlegrou ps.com...

I have a datagridview control on a form with a few of the columns being
DataGridViewCheckBox. Whenever I click on the checkbox to create a new
record I get a NullReference Exception thrown even though I check for
NULL using System.Convert.IsDbNull function.

What gives?

I'm catching the NullReferenceException, although I know it is not
correct to do for normal program flow. What is the solution?

Aug 31 '06 #3

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DataGridView DataGridViewCheckBoxCell throws NullReferenceException

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