Creating an IDictionary<string,Expression> proving difficult
I want to make a dictionary that has named LINQ Expressions, since I cannot store the expressions in my database. I will store the name of the expression that is needed,开发者_运维技巧 and a structured IList<T>
where T
is a parameter type that can be stored in the database.
But it isn't quite working how I want ... I've got the following layout. This isn't a real expression, I'm just trying to get something to compile for now..
public static class Evaluations {
public static Dictionary<string, Expression> Expressions = new Dictionary<string, Expression> {
{
"First Expression",
new Expression<Func<int, int, int>> =
(current, next) => (current + next)
}
};
}
However I am being told ... well, pretty much nothing. The compiler errors make no sense. Simply stating
This is not a variable
How can I add a System.Linq.Expressions.Expression
as the Value
of my IDictionary<string, Expression>
safely? Any suggestions?
This isn't a valid expression:
new Expression<Func<int, int, int>> =
(current, next) => (current + next)
What are you trying to assign a value to?
I think you mean:
(Expression<Func<int, int, int>>)((current, next) => current + next)
This compiles fine:
public static Dictionary<string, Expression> Expressions =
new Dictionary<string, Expression> {
{
"First Expression",
(Expression<Func<int, int, int>>)((current, next) => current + next)
}
};
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