Checking for NULL values

7 Comments

• Another solution, if you have a huge quantity of fields, is to do a concatenation with an empty string.
  
  
  
  
  
  It works for me well in VB.
  
  
  
  
  
  ( I know it's not the 'cleanest' way :-))
  
  
  
  
  
  myPhone = myDatareader("FieldPhone") + ""
  

• sometimes i use "if typeof myDBNullObject is dbnull then"
  

• With typed DataSets you can just use Is[Field]Null. e.g.: If you have a column named PersonId, you can use myRow.IsPersonIdNull.
  
  
  
  Remember, this only works in typed DataSets.
  

• Hi there I have this line of code but it seems that it's ignoring the else statement. Any help will be greatly appreciated. Thanks.
  
  
  
  If empRecord.IsNull("Email") Then
  
  empRecord("Email") = "Not Available"
  
  Else
  
  empRecord("Email") = dataReader.GetString(dataReader.GetOrdinal("Email"))
  
  End If
  

• One clean way to handle NULL values is to not bother checking for them, just convert them on the fly:
  
  
  
  myString = Convert.ToString(myDataField("SomeString"))
  
  myInteger = Convert.ToInt32(myDataField("SomeInteger"))
  
  
  
  and so on.
  

• if (cstr(rs3(1)) is null) then
  
  a= 0
  
  Response.Write a
  
  end if
  

• Thanks MarcJ your solution is great!