Question

How to convert PropertyInfo to property expression which can be used to invoke StructuralTypeConfiguration<TStructuralType>.Ignore<TProperty>(Expression<Func<TStructuralType, TProperty>> propertyExpression) method?

I tried to use Expression.Property() to construct expression but I am getting following error when I use this expression as propertyExpression parameter:

The type arguments for method cannot be inferred from the usage. Try specifying the type arguments explicitly.

This error probably refers to TProperty type parameter which I don’t know how to specify having only PropertyInfo.

I am doing this in relation to: Use Entity Framework's StructuralTypeConfiguration.Ignore() to Ignore all properties but specified set.

UPDATE

Code which is not working:

var propertyInfo = typeof(Foo).GetProperties()[0];
var expression = Expression.Default(typeof(Foo));
var expressionProperty = Expression.Property(expression, propertyInfo);
Ignore(expressionProperty);

Answer 1

var entityType = propertyInfo.DeclaringType;
var parameter = Expression.Parameter(entityType, "entity");
var property = Expression.Property(parameter, propertyInfo);
var funcType = typeof(Func<,>).MakeGenericType(entityType, propertyInfo.PropertyType);
var lambda = Expression.Lambda(funcType, property, parameter);

structureConfiguration.GetType()
   .GetMethod("Ignore")
   .MakeGenericMethod(propertyInfo.PropertyType)
   .Invoke(structureConfiguration, new[]{lambda});