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ncamoens
Starting Member
9 Posts |
 Posted - 2006-03-12 : 01:00:47
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| Hello, I am using an SQLDataReader called DrCoInfo to check if any matching records exist in a table.My code is as such:Line 119:DrCoInfo = comm1.ExecuteReader()Line 120: While DrCoInfo.Read()Line 121: If DrCoInfo("DateOfMan") <> "" Then Line 122: BValid = TrueLine 123: End IfHowever, it fails to work with the message :System.InvalidCastException: Cast from string "" to type 'Date' is not valid.Any suggestions? Thanks. |
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Kristen
Test
22859 Posts |
Posted - 2006-03-12 : 01:56:22
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| I'm not sure what a SQLDataReader is (Oracle perhaps??) but normally you have to use the syntaxMyColumn IS NULLrather than comparing it again a blank string (which is not considered to be a valid date)Kristen |
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chiragkhabaria
Master Smack Fu Yak Hacker
1907 Posts |
Posted - 2006-03-12 : 02:23:42
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quote:
Originally posted by Kristen
I'm not sure what a SQLDataReader is (Oracle perhaps??) but normally you have to use the syntax
SQLDataReader is the .net class which is used to communicate with the backend.Sucess Comes to those who Believe in Beauty of their Dream.. |
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jsmith8858
Dr. Cross Join
7423 Posts |
Posted - 2006-03-12 : 09:05:26
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| Your are comparing a date to a string. If you want to do so, you need to convert to the date to a string first.If DrCoInfo("DateOfMan").Tostring() <> "" Then Of course, converting a date to a string will never return "". Are you trying to see if the date column is null? Then you need to check for that. Don't assume that Null is the same as "".If IsDBNull(DrCoInfo("DateOfMan")) Then ... |
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ncamoens
Starting Member
9 Posts |
Posted - 2006-03-12 : 22:47:00
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| Thanks Jsmith...your first suggestion solved the problem. |
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Cast from string "" to type 'Date' is not valid