Can file polling tell the line that error

I use file polling to get batch files for processing. if it get error, Can it tell the line that invalid row?

If I understand your question correctly, You are coding this, you should put logic in your code to capture the error with the line number.

Make sure the validation code logic should be included in your processing service that you mention on the file polling port.

How do you parse the file you have received via the file polling port?

A good idea might be using a FlatFile-Dictionary and -Schema.
The document generated from the file can than be validated against this schema.
If there are errors, these should indicate which field in which row does not match the schema.

Regards,
Holger