Problem in null conversion?

Jitendra Tiwari

Hello Friends,
I m new in C# programming.
when i access data from a file.
i don't know each field has data or not.
but in my c# coding file wirte code

double value=Convert.ToDouble(dataRow["fieldValue"]);

if fieldValue is null or empty this code show exception.

Please suggest.
Thanks.

5 Replies

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Jitendra Tiwari16y ago
excelUserRecord = (from abc in dataRow
                                   where
                                   (listSchemeCode.Contains(abc.Field(ProductCode)))
                                   || (listTrnxNo.Contains(Convert.ToString((abc.Field(TransactionNo)))))
                                   || (listFolioNo.Contains((abc.Field(FolioNo))))
                                   select abc);

there is no prob field value is double or string.
problem is that if the value of TransactionNO(Bold in code block) is null linq query throw exception.
when I access each row from data row collection
Sam Hobbs16y ago
In your original question, you said the field is a double but in your last post you show a string field so which is it?
Jitendra Tiwari16y ago
hello Amit
thanks
but my problem like this

excelUserRecord = (from abc in dataRow
                                   where
                                   (listSchemeCode.Contains(abc.Field(ProductCode)))
                                   || (listTrnxNo.Contains(Convert.ToString((abc.Field(TransactionNo)))))
                                   || (listFolioNo.Contains((abc.Field(FolioNo))))
                                   select abc);

           if transaction is null form show errorrrr
Amit Choudhary16y ago
hi friend,
put a condition before using the value:
if(dataRow["fieldValur"]!=DBnull)
{
double value=Convert.ToDouble(dataRow["fieldValue"]);
}
please mark as answer if it helps.
Hirendra Sisodiya16y ago
you can use this code :
if (dataRow["fieldValue"] != null)
{
double value = Convert.ToDouble(dataRow["fieldValue"]);
}
else
{
}
thanks

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