public static object GetValue(this MemberBinding binding)
{
switch (binding.BindingType)
{
case MemberBindingType.Assignment:
var assign = (MemberAssignment)binding;
if (assign.Expression is ConstantExpression constant)
{
return(constant.Value);
}
try
{
return(CachedExpressionCompiler.Evaluate(assign.Expression));
}
catch (Exception ex)
{
//Log.Error("Error compiling expression in MemberBinding.GetValue()", ex);
//Fallback to compile and execute
var member = Expression.Convert(assign.Expression, typeof(object));
var lambda = Expression.Lambda <Func <object> >(member);
var getter = lambda.Compile();
return(getter());
}
}
return(null);
}
public static string[] GetFieldNames <T>(this Expression <Func <T, object> > expr)
{
if (expr.Body is MemberExpression member)
{
if (member.Member.DeclaringType.IsAssignableFrom(typeof(T)))
{
return new[] { member.Member.Name }
}
;
var array = CachedExpressionCompiler.Evaluate(member);
if (array is IEnumerable <string> strEnum)
{
return(strEnum.ToArray());
}
}
if (expr.Body is NewExpression newExpr)
{
return(newExpr.Arguments.OfType <MemberExpression>().Select(x => x.Member.Name).ToArray());
}
if (expr.Body is MemberInitExpression init)
{
return(init.Bindings.Select(x => x.Member.Name).ToArray());
}
if (expr.Body is NewArrayExpression newArray)
{
var constantExprs = newArray.Expressions.OfType <ConstantExpression>().ToList();
if (newArray.Expressions.Count == constantExprs.Count)
{
return(constantExprs.Select(x => x.Value.ToString()).ToArray());
}
var array = CachedExpressionCompiler.Evaluate(newArray);
if (array is string[] strArray)
{
return(strArray);
}
return(((IEnumerable)array).Cast <object>()
.Select(x => x.ToString())
.ToArray());
}
if (expr.Body is UnaryExpression unary)
{
member = unary.Operand as MemberExpression;
if (member != null)
{
return new[] { member.Member.Name }
}
;
}
throw new ArgumentException("Invalid Fields List Expression: " + expr);
}
private object ToInPartialString(Expression memberExpr, string memberName)
{
var result = CachedExpressionCompiler.Evaluate(memberExpr);
var items = Flatten(result as IEnumerable);
var dbParams = items.Map(GetValueAsParam);
var expr = $"{memberName} IN ({string.Join(",", dbParams)})";
return(new PartialString(expr));
}
protected virtual object VisitMethodCall(MethodCallExpression m)
{
if (m.Method.DeclaringType == typeof(Dynamo))
{
return(VisitDynamoMethodCall(m));
}
if (IsStaticArrayMethod(m))
{
return(VisitStaticArrayMethodCall(m));
}
if (IsEnumerableMethod(m))
{
return(VisitEnumerableMethodCall(m));
}
if (IsColumnAccess(m))
{
return(VisitColumnAccessMethod(m));
}
return(CachedExpressionCompiler.Evaluate(m));
}