Passing properties by reference in C#

I’m trying to do do the following:

GetString(
    inputString,
    ref Client.WorkPhone)

private void GetString(string inValue, ref string outValue)
{
    if (!string.IsNullOrEmpty(inValue))
    {
        outValue = inValue;
    }
}

This is giving me a compile error. I think its pretty clear what I’m trying to achieve. Basically I want GetString to copy the contents of an input string to the WorkPhone property of Client.

Is it possible to pass a property by reference?