FileHelpers change RecordLine before reading the record

Question

I am reading a huge file using FileHelpers library. I would like to change the RecordLine before reading the record like below.

   static void engine_BeforeReadRecord(object sender, BeforeReadRecordEventArgs<object> e)
    {
        if (e.RecordLine.Contains(@"\|"))
            e.RecordLine.Replace(@"\|", "");
    }

Their online help also says it is possible to change

Note: if you change the RecordLine the engine use the changed value
This can be useful in some cases but you must be carefull

But it is not working. Whether any issue in the way am i doing?

score 3 · Answer 1 · answered Dec 05 '11 at 17:39

3

Assuming RecordLine is a string, you call the .Replace() function, but this function does not modify a string inline — it returns a new string. You need to assign the result somewhere:

if (e.RecordLine.Contains(@"\|"))
    e.RecordLine = e.RecordLine.Replace(@"\|", "");

answered Dec 05 '11 at 17:39

Joel Coehoorn

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Thanks Joel, I tried this earlier and it showed an error that e.RecordLine is read-only. – Rajan R.G Dec 06 '11 at 02:51
@RajanR.G In that case you need to use both my answer and MarcosMeli's. Also - there's no need for the if statement - if the string does not contain the text, the replace call will have no effect. – Joel Coehoorn Dec 06 '11 at 03:40
Thanks Joel, the latest version with your resolution works perfectly. – Rajan R.G Dec 06 '11 at 05:12

score 0 · Answer 2 · answered Dec 05 '11 at 16:22

0

I assume that you're setting the event?

engine.BeforeReadRecord += engine_BeforeReadRecord;

answered Dec 05 '11 at 16:22

Derek Beattie

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Marcos Meli · Accepted Answer · 2015-08-03T13:28:54.113

0

With the last version of the library you can do that

http://www.filehelpers.net/download/

You can also use the INotifyRead interface:

http://www.filehelpers.net/example/EventsAndNotification/INotifyRead/

edited Aug 03 '15 at 13:28

answered Dec 05 '11 at 17:34

Marcos Meli

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Thanks Marcos, I will download the latest version and try this with assignment. – Rajan R.G Dec 06 '11 at 02:52
The latest version with Joel's answer works pefectly. Thanks for the wonderful library you have provided. – Rajan R.G Dec 06 '11 at 05:12

FileHelpers change RecordLine before reading the record

3 Answers3