What best data structures to use? [closed] - arrays

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I'm using C# to rewrite some ColdFusion code.
The CF code looks like this:
An array contains a struct that consists of two sections:
Another struct, which contains header data extracted from a data file.
A 2D array that contains the actual data from each row in the same data file.
In C#, I'm using Dictionary and Jagged Array. See the code below. Are these the best data structures to use?
// Create AllDataArray that contains HeaderAndDataDict.
Dictionary<string, object>[] AllDataArray = new Dictionary<string, object>[1];
// Create HeaderAndData Dictionary.
Dictionary<string, object> HeaderAndDataDict = new Dictionary<string, object>();
// Add HeaderAndDataDict to AllDataArray[0].
AllDataArray[0] = HeaderAndDataDict;
// Create Header Dictionary.
Dictionary<string, string> HeaderDict = new Dictionary<string, string>();
// Populate Header Dictionary
HeaderDict.Add("Create Date", "10/20/2014");
HeaderDict.Add("ABC Rank", "ALL");
HeaderDict.Add("Status", "All");
// Add Header Dictionary to HeaderAndDataDict.
HeaderAndDataDict.Add("Header", HeaderDict);
// Create jagged array.
string[][] DataJaggedArray = new string[2][];
DataJaggedArray[0] = new string[] { "aaaa0", "bbbb0", "cccc0" };
DataJaggedArray[1] = new string[] { "aaaa1", "bbbb1", "cccc1" };
// Add DataJaggedArray to HeaderAndDataDict.
HeaderAndDataDict.Add("Data", DataJaggedArray);
// Display data.
for (int a = 0; a < AllDataArray.Length; a++)
{
Console.WriteLine("AllDataArray = " + a);
foreach (var key1 in HeaderAndDataDict.Keys)
{
Console.WriteLine("key= " + key1);
if (key1.Equals("Header"))
{
var valueHeader = (Dictionary<string, string>)HeaderAndDataDict[key1];
foreach (var key2 in valueHeader.Keys)
{
Console.WriteLine("valueHeader= {0}= {1}", key2, valueHeader[key2]);
}
}
else if (key1.Equals("Data"))
{
var valueData = (string[][])HeaderAndDataDict[key1];
Console.WriteLine("valueData length= " + valueData.Length);
for (int i = 0; i < valueData.Length; i++)
{
for (int j = 0; j < valueData[i].Length; j++)
{
Console.WriteLine("valueData= i= " + i + " j= " + j + " " + valueData[i][j]);
}
}
}
}
} // AllDataArray for loop

Answer 1

Consider using an object-oriented approach to hold your data. This means creating a class that holds the headers and data rows:
public class DataItem
{
private readonly Dictionary<string, string> _headers = new Dictionary<string, string>();
private readonly List<string[]> _rows = new List<string[]>();
public IEnumerable<string> Headers
{
get { return _headers.Keys; }
}
public void AddHeader(string key, string value)
{
_headers.Add(key, value);
}
public string GetHeader(string key)
{
return _headers[key];
}
public string[] GetDataRow(int rowNumber)
{
return _rows[rowNumber];
}
public void AddDataRow(string[] row)
{
_rows.Add(row);
}
public int RowCount
{
get { return _rows.Count; }
}
}
When you have this infrastructure ready, the actual implementation becomes simpler and less error-prone:
//add data
List<DataItem> allData = new List<DataItem>();
var dataItem = new DataItem();
dataItem.AddHeader("Create Date", "10/20/2014");
dataItem.AddHeader("ABC Rank", "ALL");
dataItem.AddHeader("Status", "All");
dataItem.AddDataRow(new [] {"aaaa0", "bbbb0", "cccc0"});
dataItem.AddDataRow(new[] {"aaaa1", "bbbb1", "cccc1"});
allData.Add(dataItem);
//display data
foreach (var item in allData)
{
Console.WriteLine("New item:");
foreach (var header in item.Headers)
{
Console.WriteLine("{0}: {1}", header, item.GetHeader(header));
}
for (int i = 0; i < item.RowCount; i++)
{
var row = item.GetDataRow(i);
for (int j = 0; j < row.Length; j++)
{
Console.WriteLine("Cell ({0}, {1}): {2}", i, j, row[j]);
}
}
}
Additionaly, if you like to, you could move the printing code to within the data item class:
public class DataItem
{
public void Print()
{
Console.WriteLine("New item:");
foreach (var header in Headers)
{
Console.WriteLine("{0}: {1}", header, GetHeader(header));
}
for (int i = 0; i < RowCount; i++)
{
var row = GetDataRow(i);
for (int j = 0; j < row.Length; j++)
{
Console.WriteLine("Cell ({0}, {1}): {2}", i, j, row[j]);
}
}
}
}
Then using it like this:
//display data
foreach (var item in allData)
{
item.Print();
}
This will have the advantage that if you require printing from somewhere else in your program you can do it more easily. This can also work for other things like loading data from a text file, or saving it back.
Update
To access your data using LINQ, here is an example that filters on rows and headers, then sorts the results by the value in the Create Date header.
var query = from item in allData
where item.GetHeader("Status") == "Status 1"
&& item.GetHeader("ABC Rank") == "3"
&& item.GetDataRow(1).Contains("bbbb1")
orderby item.GetHeader("Create Date")
select item;
foreach (var item in query)
item.Print();

Answer 2

They are valid choices.
I don't think there is a "best" solution for all usages
It depends on how you plan to access them (number of read / write operations, thread safety, ...).