Can I configure a strongly typed data set to use nullable values?
If I have a strongly typed data table with a column for values of type Int32
, and 开发者_开发问答this column allows nulls, then I'll get an exception if I do this for a row where the value is null:
int value = row.CustomValue;
Instead I need to do this:
if (!row.IsCustomValueNull()) {
int value = row.CustomValue;
// do something with this value
}
Ideally I would like to be able to do this:
int? value = row.CustomValue;
Of course I could always write my own method, something like GetCustomValueOrNull
; but it'd be preferable if the property auto-generated for the column itself simply returned a nullable. Is this possible?
Unfortunately, this is not supported.
However, you can make your own wrapper property, like this:
public int? CustomValue {
get { return IsCustomValueqlNull() ? new int?() : CustomValueSql; }
set {
if (value == null)
SetCustomValueSqlNull();
else
CustomValueSql = value.Value;
}
}
Where CustomValueSql
is the actually column name.
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