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Convert csv to double list with c#

with the following code Im trying to read a csv file that contains double values and convert it into a list. If I want to print that list The output just contains "system.collections.generic.list1 system.string". What is wrong in my code?
var filePath = #"C:\Users\amuenal\Desktop\Uni\test.csv";
var contents = File.ReadAllText(filePath).Split(';');
var csv = from line in contents
select line.Split(';').ToList();
foreach (var i in csv)
{
Console.WriteLine(i);
}

You got a couple things wrong with your code. First, you should most likely be using ReadAllLines() instead of ReadAllText(). Secondly, your LINQ query was returning a List<List<string>> which I imagine is not what you wanted. I would try something like this:
var filePath = #"C:\Users\amuenal\Desktop\Uni\test.csv";
//iterate through all the rows
foreach (var row in File.ReadAllLines(filePath))
{
//iterate through each column in each row
foreach(var col in row.Split(';'))
{
Console.WriteLine(col);
}
}

This should do good. Hope this helps.
var filePath = #"C:\Users\amuenal\Desktop\Uni\test.csv";
var contents = File.ReadAllLines(filePath);
var csv = (from line in contents
select line.Split(';')).SelectMany(x1 => x1);
foreach (var i in csv)
{
Console.WriteLine(i);
}

csv is an IEnumerable of a List of string. (in other words, each "i" is a list of string).
You need two loops:
foreach (var list in csv)
{
foreach(var str in list)
{
Console.WriteLine(str);
}
}

Remove all elements from an ArrayList that contains string

I've been trying to figure out how to remove elements in my ArrayList where the value contains some text string.
My Array could look like this:
[0] "\"MAERSKA.CO\",N/A,N/A,N/A,N/A,N/A,N/A"
[1] "\"GEN.COABB.ST\",N/A,N/A,N/A,N/A,N/A,N/A"
[2] "\"ARCM.ST\",\"Arcam AB\",330.00,330.50,332.00,330.50,330.00"
And my ArrayList is created like this:
string stringToRemove = "NA";
ArrayList rows = new ArrayList(csvData.Replace("\r", "").Split('\n'));
So the question is how I delete all entries that contains "NA".
I have tried the RemoveAt or RemoveAll with several combinations of Contains but i cant seem to get the code right.
I do not want to make a new Array if it can be avoided.
Regards
Flemming

If you want to reduce your ArrayList before instantiate your variable, consider using LINQ:
ArrayList rows = new ArrayList(csvData.Replace("\r", "").Split('\n').Where(r => !r.Contains(stringToRemove)).ToList());
If you want to reduce your ArrayList after instantiation, you can try this:
for (int i = 0; i < rows.Count; i++)
{
var row = (string)rows[i];
if (row.Contains(stringToRemove))
{
rows.RemoveAt(i);
i--;
}
}

The following code creates a list as output containing all strings except "N/A":
var outputs = new List<string>();
foreach (var item in input)
{
var splitted = item.Split(',');
foreach (var splt in splitted)
{
if (splt != "N/A")
{
outputs.Add(splt);
}
}
}
The input is your array.

Clearing a List<string> removes all values from Dictionary List of Strings, C#

Trying to read a csv file, and take the first word in the stream, throw it in to a dictionary while the following words get added to a list in that dictionary.
However, I find that (during debugging) when, inside my loop I decide to clear my list, all of the values it had added to the dictionary previously also get cleared. I guess I am mistaken in assuming it makes a copy of the list, it is actually just referencing that same list? Should I be creating a new list with every iteration? Code below:
public class TestScript : MonoBehaviour {
// Use this for initialization
void Start() {
Dictionary<string, List<string>> theDatabase = new Dictionary<string, List<string>>();
string word;
string delimStr = ",.:";
char[] delimiter = delimStr.ToCharArray();
List<string> theList = new List<string>();
using (StreamReader reader = new StreamReader("testComma.csv")) {
while (true) {
//Begin reading lines
string line = reader.ReadLine();
if (line == null) {
break;
}
//Begin splitting lines, adding to array.
string[] split2 = line.Split(delimiter, StringSplitOptions.RemoveEmptyEntries);
//Loop to hold the first word in the stream
for(int i = 0; i <= 0; i++) {
word = split2[i];
//loop to hold the following words in to list.
for (int y = 1; y < split2.Length; y++) {
theList.Add(split2[y]);
}
//Add word/list combo in to the database
theDatabase.Add(word, theList);
//clear the list.
theList.Clear();
}
}
}
foreach (KeyValuePair<string, List<string>> pair in theDatabase) {
string keys;
List<string> values;
keys = pair.Key;
values = pair.Value;
print(keys + " = " + values);
}
}
}
The bottom foreach loop is just so I can see the results. Also, any critique is welcome in regards to how this is written, as I'm a beginner.

Yes, you're adding the same object to your dictionary.
You can just change :
theDatabase.Add(word, theList);
To :
theDatabase.Add(word, theList.ToList());
Method ToList() makes shallow copy of your List<T>

C# is pass by reference.
So, theList and the list in your Dictionary are the same object.
The simplest solution is to stop clearing your List and create a new one every time instead:
for(int i = 0; i <= 0; i++) {
List<string> theList = new List<string>(); // it is in a loop now
word = split2[i];
//loop to hold the following words in to list.
for (int y = 1; y < split2.Length; y++) {
theList.Add(split2[y]);
}
//Add word/list combo in to the database
theDatabase.Add(word, theList);
//clear the list.
//theList.Clear(); - not required anymore
}
It is more readable and clear solution: create a list, insert items, paste a list into the dictionary, continue the iteration.
It is also much more performant since there is no List clearing - List<T>.Clear() is a linear operation, which takes O(n) operations.

Yes, as everyone says, lists are reference types. You need to make a copy to avoid the .Clear() clearing all the lists.
You could always write your code like this:
void Start()
{
string delimStr = ",.:";
Dictionary<string, List<string>> theDatabase =
File
.ReadAllLines("testComma.csv")
.Select(line => line.Split(delimStr.ToCharArray(), StringSplitOptions.RemoveEmptyEntries))
.ToDictionary(x => x[0], x => x.Skip(1).ToList());
/* foreach here */
}
}
This doesn't have the problem with the list references.

Directory.GetFiles error

my code
private void m1()
{
List<string> list = new List<string>();
foreach (string str in Directory.GetFiles("a1"))
{
if (Path.GetExtension(str).Contains("txt")) -- get all txt file in a1 folder
{
list.Add(Path.GetFileNameWithoutExtension(str));
}
}
base.SuspendLayout();
this.Combobox_1.Items.AddRange(list.ToArray());
base.ResumeLayout();
}
but combobox cannot list txt file in folder a1
Please helpme.

i think there is no need to store values first in a list and then add to a combobox.
it can be done directly to a combobox.
i have replace relative path a1 to a real one to let you understand easily.
foreach (string str in Directory.GetFiles(#"D:\"))
{
if (System.IO.Path.GetExtension(str).Contains("txt"))
{
this.Combobox_1.Items.Add(System.IO.Path.GetFileNameWithoutExtension(str));
}
}

How to display form variables based on variable name

I have a list of variable names, lets say:
List<string> list = new List<string>();
list.Add("size");
list.Add("width");
list.Add("name");
list.Add("zip");
and i have text controls with those exact names, is there a way to loop through the list and only display what the value of the text control that i am asking for, like lets say something like this:
foreach (string txtctl in list)
{
Response.Write(Request.Form[txtctl]);
}
When i run this code the value just displays blank. Any suggestions?

string str = "";
foreach (string item in list)
{
TextBox txt = (TextBox)Form.FindControl(item);
if (txt != null)
{
str += item+":"+ txt.Text+"<br>";
}
}
Response.Write(str);