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String was not recognized as a valid DateTime error on Convert.ToDateTime

I loading values from the database to a dataset. When there is a null in the datetime column, the FormatException is thrown - String was not recognized as a valid DateTime. How do I handle this problem in the following method.

public dsInventory PopulateClass(DataSet ds)
{
DataTable dt = new DataTable();
dt = ds.Tables[0];
dsInventory dsI = new dsInventory();
foreach (DataRow dtrow in dt.Rows)
{
//Error on these lines when a null is available
dsI.MtlDueDate = Convert.ToDateTime(dtrow["MtlDueDate"].ToString());
dsI.MtlReceiptDate = Convert.ToDateTime(dtrow["MtlReceiptDate"].ToString());

}
return dsI;
}

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Angelp1ay

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ChloesDad

Use DBNull.Value.Equals on the object without converting it to a string.

Here's an example:
if (! DBNull.Value.Equals(row[fieldName]))
{
//not null
}
else
{
//null
}

Angelp1ay

If you want your field to be a plain DateTime instead of the Nullable DateTime (DateTime?) I proposed then you need to do what ChloesDad said and probably want to set your field to DateTime.MinValue.

Personally I think DateTime? represents your data semantics more correctly.

Dmitry G

First, you may need to check values for DbNull:

if (row["myCol"] != DBNull.Value)
{
         ... //some code
}
else
{

}

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In 'else' you may set your dateTime value to DateTime.MinValue or DateTime.MaxValue instead.

Other option would be to use Nullable of DateTime.

Monica P

Declaring as like below ., will accept the nothing in date field
Try like this in your code and check

 Dim DOB As Nullable(Of Date) = Date.Now
    DOB = Nothing

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