Unable to cast object of type 'System.DBNull' to type 'System.Byte[]

Asked Oct 21 '19 at 19:26

Active Oct 21 '19 at 19:26

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I'm getting the following error and I'm having some difficulty on how I can write the following snippet of code bellow to prevent the following error before casting, I tried the following solution and no luck...

Error: Unable to cast object of type 'System.DBNull' to type 'System.Byte[]

byte[] pictureAsByteArray = (byte[])reader.GetValue(ordinals.GetOrdinal("xxxSignature"));

Solution Doesn't work:

if ((reader.GetValue(ordinals.GetOrdinal("xxxSignature")!= null))
else() then casting

edited Oct 21 '19 at 19:26

maccettura

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asked Oct 21 '19 at 19:26

Stacey

FYI `DBNull` is not the same thing as `null`... – maccettura Oct 21 '19 at 19:27
`if ((reader.GetValue(ordinals.GetOrdinal("xxxSignature")!= DBNull.Value))` – hawkstrider Oct 21 '19 at 19:27
What is the definition of `ordinals` – Rakesh Oct 21 '19 at 19:34
the ordinals is a Dictionary. – Stacey Oct 21 '19 at 19:37
Then check in ordinals if the key "xxxSignature" exists, and only if it exists should you go into `byte[] pictureAsByteArray = (byte[])reader.GetValue(ordinals.GetOrdinal("xxxSignature"));` – Rakesh Oct 21 '19 at 20:07

Unable to cast object of type 'System.DBNull' to type 'System.Byte[]

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