C# create an array with iteration

Question

I need to create a new bi-dimensional String array like this one:

-- Create Header and Data

 String[] Header ={"Item","Description", "Qty","Unit Price","Price"};

 String[][] data = {
     new String[]{"Spire.Doc for .NET",".NET Word Component","1","$799.00","$799.00"},
     new String[]{"Spire.XLS for .NET",".NET Excel Component","2","$799.00","$1,598.00"},
     new String[]{"Spire.Office for .NET",".NET Office Component","1","$1,899.00","$1,899.00"},
     new String[]{"Spire.PDF for .NET",".NET PDFComponent","2","$599.00","$1,198.00"},
 };

But "data" is declared on the code, the problem is that I need to declare "data" with the data (sorry about repeating "data" multiple times) of an unknown length array[n], so the code could work like:

 String[][] data = {
     new String[]{"arrayFromFunction[0].data1","arrayFromFunction[0].data2","arrayFromFunction[0].data3","arrayFromFunction[0].data4","arrayFromFunction[0].data5"},
     new String[]{"arrayFromFunction[1].data1","arrayFromFunction[1].data2","arrayFromFunction[1].data3","arrayFromFunction[1].data4","arrayFromFunction[1].data5"},
     ...
     new String[]{"arrayFromFunction[n].data1","arrayFromFunction[n].data2","arrayFromFunction[n].data3","arrayFromFunction[n].data4","arrayFromFunction[n].data5"}
};

But I don't know how to iterate INSIDE the declaration of String[][] data or how to save the iterator (n) to use it inside data declaration.

Hope I've explained well and thanks for your help.

That's not a 2D array, that's a jagged array. An array containing string arrays. What you posted doesn't have any iteration code or any iterators either. — Panagiotis Kanavos, Jan 05 '21 at 20:17
This shows an example of using `for` loops to iterate a jagged array: (https://www.geeksforgeeks.org/c-sharp-jagged-arrays/) — Ryan Wilson, Jan 05 '21 at 20:18
I don't think it's clear what you're trying to achieve. You're taking a jagged array (`string[][]`) `arrayFromFunction` and trying to copy it to a new `string[][]` called `data`? Also, where does the `Header` come into it? — Connell.O'Donnell, Jan 05 '21 at 20:21

score 2 · Answer 1 · edited Jan 05 '21 at 22:52

2

So you have structured data somewhere and you want to de-structure it? That goes against any modern programming principle where you bind structured data to your view and let the framework take care of the rest.

That said, it's relatively trivial to achieve:

var data = arrayFromFunction.Select(w => new[] { w.data1, w.data2, w.data3, w.data4, w.data5 }).ToArray();

edited Jan 05 '21 at 22:52

Jean-François Fabre

137,073
23
153
219

answered Jan 05 '21 at 20:19

Blindy

65,249
10
91
131

score -1 · Answer 2 · answered Jan 05 '21 at 20:24

But I don't know how to iterate INSIDE the declaration of String[][] data or how to save the iterator (n) to use it inside data declaration.

You don't; this is a compile time code block you've written here. It is a constant hard baked into your program when you hit "build", with no ability to cope with your arrayFromFunction having a variable number of elements

Well..

I suppose you could write a program that generates and compiles C# on the fly

But it seems needlessly more complex than using e.g a List<string> and looping over the arrayFromFunction array and adding items to the list:

foreach(var item in arrayFromFunction)
  someList.Add(new []{ item.data1, item.data2 ... });

or writing a LINQ statement to project the arrayFromFunction to an enumerable of string arrays

var someList = arrayFromFunction.Select(item => new []{ item.data1, item.data2 ... }).ToList();

the second option looks better and easier, thank you – Gyffet Jan 05 '21 at 22:35 — Gyffet, Jan 05 '21 at 22:35

C# create an array with iteration

2 Answers2