Foreach Dynamic Linq Multiple Columns

Question

Hello I'm using dynamic linq and I have query like this one:

var result = DataContext.Table
    .Where("Code == @0", CodeId)
    .Select("new(SGL AS First, DBL AS Second)");

How can I loop the result?

I'm using something like this code but it doesn't work:

foreach (var item in result)
{
    total = subtotal + Int32.Parse(item.ToString()) * 2
}

It returns the following error:

The input string does not have the correct format.

The code you have highlighted is not your issue... I believe the issue is inside your foreach — austin wernli, Jun 04 '15 at 22:43
How can I extract the First value and Second value inside foreach loop? That's what I want to know — Luis Lora, Jun 04 '15 at 22:45
There is nothing wrong with the code you have posted. There must be something wrong with the contents of the `foreach` loop. Post that and we can help you, until then I'm flagging this question as off-topic. — DavidG, Jun 04 '15 at 22:52
This is my foreach `foreach (var item in result) { total = subtotal + Int32.Parse(item.ToString()) * 2; }` — Luis Lora, Jun 04 '15 at 22:57
Put a break-point on the foreach statement and check what type/data result has. I'm pretty sure it cannot be converted directly to an integer, since you are selecting two columns. The result is probably an IEnumerable of a dictionary or something. — HaukurHaf, Jun 04 '15 at 23:08

score 1 · Accepted Answer · answered Jun 04 '15 at 23:07

1

The problem is in your foreach loop, not with the dynamic linq. This line:

total = subtotal + Int32.Parse(item.ToString()) * 2

Is going to convert your object to a string, which will look something like this:

{First=XXX, Second=YYY}

And if you pass that directly to Int32.Parse you will get the error you describe.

Instead you want to work on the properties of the object. One way is to cast the object to a dynamic value, then you can get the properties as you would any other object:

dynamic obj = resultItem;
total = subtotal + Int32.Parse(obj.First) * 2

answered Jun 04 '15 at 23:07

DavidG

113,891
12
217
223

yes, selected two fields and he is trying to convert them into Int – Yuri Jun 05 '15 at 12:43
Hello I used your code and I got this error: The operator '*' can not be applied to operands of type ' DynamicClass1 ' and ' int ' Thanks for your reply – Luis Lora Jun 05 '15 at 13:54
@LuisLora What are the types of `total` and `subtotal`? – DavidG Jun 05 '15 at 13:59
@LuisLora Then that error message makes no sense. What code is giving you that error? – DavidG Jun 05 '15 at 14:07
@DavidG the code is working I had another mistake in my code. Thanks – Luis Lora Jun 05 '15 at 14:14

score 0 · Answer 2 · answered Jun 05 '15 at 12:48

0

you should try to

foreach (var item in result)
{
  total = subtotal + Int32.Parse(item.First) * 2
}

answered Jun 05 '15 at 12:48

Yuri

2,820
4
28
40

You can't do this when the type is `object`. – DavidG Jun 05 '15 at 13:58

Foreach Dynamic Linq Multiple Columns

2 Answers2