[GENERAL] Double types

[Hall, Samuel L (Sam)]

I have an application that writes an Excel Spreadsheet to postgres. For the 
values that go in number fields, I check the Excel values for dbnull and set 
the parameters to 0, like this: cmd.Parameters(9).Value = 0. Npgsql throws an 
error "format specifier was invalid" If I do this: cmd.Parameters(9).Value = 
convert.todouble(0) then it works fine.
Visual Basic 2010, Postgres 9.1, npgsql 2.0.12.0

Could somebody please explain this behavior?

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