how to address object dynamically in c#

Question

I have a need to build some search criteria using the inputs user entered.

string searchText1 = "";
string searchText2 = "";
string searchText3 = "";

searchText1 = scCB1.Text + op1.Text + cr1.Text;
searchText2 = scCB2.Text + op2.Text + cr2.Text;
searchText3 = scCB3.Text + op3.Text + cr3.Text;

where scCB1, op1, cr1, ... are the combobox and text fields on GUI.

Is there a way I could use a loop to replace the hard coded statements (they look awkward)?

For (i = 0; i < 3; i++)
{  
   //    searchText(i) = scCB(i).Text + op(i).Text +cr(i).Text)
}

As a rookie in programming, I understand if I display and build only one set of fields on GUI, then I'll be able to loop in the code. But I am curious how i could address the name of the objects dynamically. Thanks in advance for all your help!

`scCB(i)` have you considered using arrays? The syntax is essentially what you want: `scCBArray[i]` — Flater, Aug 06 '18 at 07:33
You´re on the right track already, just use an array or a list instead of three different variables. — MakePeaceGreatAgain, Aug 06 '18 at 07:36
I'm not quite sure why this is being downvoted. The question is clear, well-formed and shows a reasonable usage and expectation. While the solution is fairly simple, this is a question that most developers will have asked themselves at some point and thus is a relevant question for posterity's sake. — Flater, Aug 06 '18 at 07:41

Ashkan Mobayen Khiabani · Answer 1 · 2018-08-06T07:46:00.123

1

Assuming that the controls are on a GroubBox named options:

string[] searchText = new string[3];
for(int i = 1; i<=3; i++)
   {
        searchText[i - 1] = options.Control["scCB" + i.Tostring()] +
                        options.Control["ops" + i.Tostring()] +
                        options.Control["cr" + i.Tostring()];
   }

edited Aug 06 '18 at 07:46

answered Aug 06 '18 at 07:25

Ashkan Mobayen Khiabani

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@HimBromBeere I edited my answer – Ashkan Mobayen Khiabani Aug 06 '18 at 07:41
1

Far easier would be to simply loop from zero to 2. – MakePeaceGreatAgain Aug 06 '18 at 07:45
@HimBromBeere in here `options.Control["scCB" + i.Tostring()]` control names start from 1. so we should have `i-1` where I did, or `i+1` when getting controls by name `options.Control["scCB" + (i + 1).Tostring()]`; – Ashkan Mobayen Khiabani Aug 06 '18 at 07:47

score 1 · Answer 2 · answered Aug 06 '18 at 07:27

1

I would suggest to make an array containing your text boxes and other elements, this way your can easily reference them inside a loop:

TextBox[] boxes = {scCB1, scCB2, scCB3}; // do same for op1..3 and cr1..3
for (int i = 0; i < 3; i++)
{     
  string searchText = boxes[i].Text + ops[i].Text + cr[i].Text;
}

answered Aug 06 '18 at 07:27

Matěj Štágl

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`searchText`s will have to be in a collection as well. And please explain why to use array and not `List`? – Guy Aug 06 '18 at 07:29
@Guy, I am suggesting to use an array instead of a list as I assume the count of textboxes to be determined and not to be changed on runtime. If you would add textboxes somewhere in the process then sure, use list or arrayList. – Matěj Štágl Aug 06 '18 at 07:30
1

@Guy: Most of the argument between array/list has evaporated since they share most of their features by both of them implementing `IEnumerable`. It's easy to jump from one to the other, neither option locks you in. However, as OP wants an indexed approach, arrays are the go-to solution. Note that you can index a list (`myList[i]`), but it's more idiomatic to refer to an array when focusing on indexed element retrieval. – Flater Aug 06 '18 at 07:35
To the guy downvoting my answer: please explain the reason. – Matěj Štágl Aug 06 '18 at 07:39
2

Nobody down-votes your answer. – MakePeaceGreatAgain Aug 06 '18 at 07:40

how to address object dynamically in c#

2 Answers2