LINQ Expression> equavalent of .Contains()

Question

Has anybody got an idea of how to create a .Contains(string) function using Linq Expressions, or even create a predicate to accomplish this

public static Express         


        

Answer 1

public static Expression> StringContains(string subString)
{
    MethodInfo contains = typeof(string).GetMethod("Contains");
    ParameterExpression param = Expression.Parameter(typeof(string), "s");
    var call = Expression.Call(param, contains, Expression.Constant(subString, typeof(string)));
    return Expression.Lambda>(call, param);
}

...

// s => s.Contains("hello")
Expression> predicate = StringContains("hello");

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Looking at this many years later, I suddenly realize there's a much simpler approach for this specific example:

Expression> predicate = s => s.Contains("hello");