Re: stringOperand + null = ?

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Mark Chambers <no_spam@xxxxxxxxxxx> wrote:
Hi there,

In the expression A + B where A is a string and B isn't, I know that
"B.ToString()" will be called and the results concatenated. If B is null
however does the standard guarantee that "String.Empty" will be used
instead. Thanks.

Yup, the spec says:

<quote>
If an operand of string concatenation is null, an empty string is
substituted. Otherwise, any non-string argument is converted to its
string representation by invoking the virtual ToString method inherited
from type object. If ToString returns null, an empty string is
substituted.
</quote>

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