Shortest way to check for null and assign another value if not

I am pulling varchar values out of a DB and want to set the string I am assigning them to as "" if they are null. I'm currently doing it like this:

if (string.IsNullOrEmpty(planRec.approved_by) == true)
  this.approved_by = "";
else
  this.approved_by = planRec.approved_by.toString();

There seems like there should be a way to do this in a single line something like:

this.approved_by = "" || planRec.approved_by.toString();

However I can't find an optimal way to do this. Is there a better way or is what I have the best way to do it?

Try this:

this.approved_by = IsNullOrEmpty(planRec.approved_by) ? "" : planRec.approved_by.toString();

You can also use the null-coalescing operator as other have said - since no one has given an example that works with your code here is one:

this.approved_by = planRec.approved_by ?? planRec.approved_by.toString();

But this example only works since a possible value for this.approved_by is the same as one of the potential values that you wish to set it to. For all other cases you will need to use the conditional operator as I showed in my first example.

The coalesce operator (??) is what you want, I believe.

You are looking for the C# coalesce operator: ??. This operator takes a left and right argument. If the left hand side of the operator is null or a nullable with no value it will return the right argument. Otherwise it will return the left.

var x = somePossiblyNullValue ?? valueIfNull;

Starting with C# 8.0, you can use the ??= operator to replace the code of the form

if (variable is null)
{
    variable = expression;
}

with the following code:

variable ??= expression;

More information is here

My guess is the best you can come up with is

this.approved_by = IsNullOrEmpty(planRec.approved_by) ? string.Empty
                                                      : planRec.approved_by.ToString();

Of course since you're hinting at the fact that approved_by is an object (which cannot equal ""), this would be rewritten as

this.approved_by = (planRec.approved_by ?? string.Empty).ToString();