Develop Reference

write a C# code for extracting a .csv file, if i give one of the element of first column, i get the corresponding values of the other two columns

this is my .csv file:
Apple,rose,tiger
Mango,lily,cheetah
Banana,sunflower,lion
Apple,marigold,cat
input: Mango (i write it in the text box)
desired output:
Flower = lily; Animal = cheetah
similarly,
input: Apple
desired output:
Flower = rose,marigold; Animal = tiger,cat
this is the code i have written:
private void button1_Click(object sender, EventArgs e)
{
using (var reader = new StreamReader(#"C:\asp_net\abc.csv"))
{
List<string> listA = new List<string>();
List<string> listB = new List<string>();
List<string> listC = new List<string>();
while (!reader.EndOfStream)
{
var line = reader.ReadLine();
var values = line.Split(',');
listA.Add(values[0]);
listB.Add(values[1]);
listC.Add(values[2]);
}
string checkThis = obj.SearchSenSig(textBox1.Text);
if (listA.Any(checkThis.Contains))
{
int count = listA.Where(x => x.Equals(checkThis)).Count();
if (count == 1)
{
int index = listA.IndexOf(checkThis);
var firstItem = listB.ElementAt(index);
var secondItem = listC.ElementAt(index);
MessageBox.Show(String.Format("receiver = {0}, url = {1}", firstItem, secondItem));
}
else
{
foreach (string item in listA)
{
int i = listA.IndexOf(item);
bool result = item.Equals(checkThis);
if (result)
{
List<string> myCollection1 = new List<string>();
myCollection1.Add(listB.ElementAt(i));
string firstItem = string.Join(",", myCollection1);
List<string> myCollection2 = new List<string>();
myCollection2.Add(listC.ElementAt(i));
string secondItem = string.Join(",", myCollection2);
MessageBox.Show(String.Format("Flower = {0}, Animal = {1}", firstItem, secondItem));
}
}
}
}
else
{
MessageBox.Show("The search element does not exists.");
}
}
Still i am not getting the desired output. Please help.

Instead of creating a different list for each column, create a single class to hold an entire row data:
class Data // I'll bet you can find a better name for this class...
{
public string Fruit {get;set;}
public string Flower {get;set;}
public string Animal {get;set;}
}
and populate a list of this class:
private List<Data> data = new List<Data>(); // note: this is a field, not a local variable.
Populating this list should be done only once, in the constructor or in the form_load event:
while (!reader.EndOfStream)
{
var line = reader.ReadLine();
var values = line.Split(',');
data.Add(
new Data()
{
Fruit = values[0],
Flower = values[1],
Animal = values[2]
}
);
}
Now all you have to do in the button_click event handler is get all the items corresponding to your search string. Assuming you are only searching for fruits using the FindAll method and display the results:
var result = data.FindAll(d => d.Fruit == searchString);
This will return a list of Data where the Fruit property contains the same string as searchString. use linq and string.Join to format the results into a string:
var resultString = $"Flower = {string.Join(",", result.Select(r => r.Flower))}; Animal = {string.Join(",", result.Select(r => r.Animal))}";

foreach and index in .ToDictionary C#

I am web-scraping some data and trying to write the scraped data to a json file using C# newtonsoft.Json
I get stuck when writing a foreach in my .ToDictionary function as well as not being able to ++ an index into my .ToDictionary function.
My class:
public class JsonParametersData
{
public bool required { get; set; }
public bool list { get; set; }
public List<string> options { get; set; }
}
My arrays
var jsonData = new List<Dictionary<string, Dictionary<string, JsonParametersData>>>();
var moduleParameters = new List<string>();
var parameterOptionsArray = new List<List<string>>();
var parameterOptions = new List<string>();
var requiredArray = new List<bool>();
var listArray = new List<bool>();
string moduleName = item.Attributes["href"].Value.Replace("_module.html", "");
The code which is commented shows what I am trying to do.
int index = 0;
jsonData.Add(new Dictionary<string, Dictionary<string, JsonParametersData>>()
{
{
moduleName,
moduleParameters
.ToDictionary(n => n,
n => new JsonParametersData
{
required = requiredArray[index],
list = listArray[index],
options = new List<string>() { "option1", "option2" },
/*
foreach (var parameteroption in parameterOptionsArray[index])
{
options.Add(parameteroption);
}
index++;
*/
})
}
});
string json = JsonConvert.SerializeObject(jsonData.ToArray());
//write string to file
System.IO.File.WriteAllText(#"path", json);

Your parameterOptionsArray is not an Array, but a List of lists.
The thing is that parameterOptionsArray[index] is a List, not a string. So you should use AddRange() instead of Add().
parameterOptionsArray.Foreach(parameteroption => options.AddRange(parameteroption));

As I´ve written in the comments you can make only assignments in an object-initializer. Thus the following is allowed:
var a = new { MyMember = anInstance }
whilst this is not:
var a = new { MyMember = anInstance, anInstance.DoSomething() };
That´s one of those cases where you should not use Linq at all, as it leads to more confusion than it helps. Instead use a good old-styled loop:
int index = 0;
var innerDict = new Dictionary<string, JsonParametersData>();
foreach(var name in moduleParameters)
{
innerDict[name] = new JsonParametersData
{
required = requiredArray[index],
list = listArray[index],
options = new List<string>() { "option1", "option2" },
}
innerDict[name].Options.AddRange(parameterOptionsArray[index]);
index++;
}
var dict = new Dictionary<string, Dictionary<string, JsonParametersData>>();
dict[moduleName] = innerDict;
jsonData.Add(dict);
string json = JsonConvert.SerializeObject(jsonData.ToArray());

You appear to have a jagged array in parameterOptionsArray. You can make use of SelectMany here. Perhaps following sample can help:
string[][] parameterOptionsArray = new string[2][];
parameterOptionsArray[0] = new string[2];
parameterOptionsArray[0][0] = "1";
parameterOptionsArray[0][1] = "2";
parameterOptionsArray[1] = new string[2];
parameterOptionsArray[1][0] = "3";
parameterOptionsArray[1][1] = "4";
var testing = new {options = parameterOptionsArray.SelectMany(x => x).ToList()};
testing.options.ForEach(x => Console.WriteLine(x));

C# List Split and Join Specific Length

I pull object in MSSQL and i would like to try below
List for example
Num1 = 123123
Num2 = 2222
Num3 = 3456734567
Num4 = 4669321469321
How do i combine this list since the length is not the same?
Expected Result :
CombinedNum = 123223456746693211232234567469321
Code i tryed :
List<string> first4List = new List<string>();
List<string> Num_1List = new List<string>();
List<string> Num_2List = new List<string>();
List<string> Num_3List = new List<string>();
List<string> Num_4List = new List<string>();
while (render.Read())
{
first4List.Add(render["N1"].ToString());
last4List.Add(render["N2"].ToString());
HashList.Add(render["N3"].ToString());
FlagList.Add(render["N4"].ToString());
ReasonList.Add(render["N5"].ToString());
render.Close();

If what you are trying to achieve is to generate a string that is a combination of all elements in a list then try the below.
var Num_1List = new List<string>
{
"123123", "2222", "3456734567", "4669321469321"
};
var combinedString = Num_1List.Aggregate((current, part) => current + part);

Create an array of list

I want to create a array of list which will contain a string and a list of arrays.
example:
I want like this one.
list(0) --- string value list(0) ---list(0) - string value
list(0) ----list(1) - string value
list(1) --- string value list(1) ---list(0) - string value
list(1) ----list(1) - string value
and so on..
how will i declare?
i tried:
List<List<String>> list = new List<List<string>>(); // but it didn't work.
List<string[]> arrayList = new List<string[]>(); // again it didn't work..
is this possible to declare?
if so how?

Isnt this a Dictionary<string, string[]>?
var x = new Dictionary<string, string[]>();
x.Add("string1", new string[] {"a", "b", "c"})
Then you can have a list of that dictionary.
var list = new List<Dictionary<string, string[]>>();
list.Add(x);

Does this work for you?
public class Tree<T> : List<Tree<T>>
{
public Tree(T value) { this.Value = value; }
public T Value { get; set; }
}
It's not an array, but a list, but it's much the same structure.
You can then assign it like this:
var trees = new []
{
new Tree<string>("Branch 1")
{
new Tree<string>("Leaf 1.1"),
new Tree<string>("Leaf 1.2"),
},
new Tree<string>("Branch 2")
{
new Tree<string>("Leaf 2.1"),
new Tree<string>("Leaf 2.2"),
},
};

As I can see in your data structure you've asked for A List containing two List's and all of them are of same string type then you should go with Dictionary. As a List can of of single type and you can add a single value to it at a time. Try Dictionary,
Dictionary<string, string> dictionary = new Dictionary<string, string>();
or if you want a Dictionary containing List of string,
Dictionary<List<string>, List<string>> dictionary = new Dictionary<List<string>, List<string>>();

try this
List<List<String>> str_2d_list = new List<List<String>>();
List<String> l1 = new List<string>();
l1.Add("l1.string1");
l1.Add("l1,string2");
List<String> l2 = new List<string>();
l2.Add("l2.string1");
l2.Add("l2,string2");
str_2d_list.Add(l1);
str_2d_list.Add(l2);

if you want to create an array of a string and a list, use the second way in the code. but if you want a list of list use first way in the code.
using System;
using System.Collections.Generic;
namespace ConsoleApplication1
{
internal class Program
{
private static void Main(string[] args)
{
// an example of list of strings
List<string> names = new List<string>();
names.Add("Mike");
names.Add("Sarah");
List<string> families = new List<string>();
families.Add("Ahmadi");
families.Add("Ghasemi");
// 1st way
List<List<string>> outsideList = new List<List<string>>();
outsideList.Add(names);
outsideList.Add(families);
// 2nd way
Dictionary<string, List<string>> d = new Dictionary<string, List<string>>();
d.Add("first", names);
d.Add("second", families);
// how to access list<list<>>
foreach (List<string> list in outsideList)
{
foreach (string s in list)
Console.WriteLine(s);
}
// how to access list inside dictionary
foreach (List<string> list in d.Values)
{
foreach (string s in list)
Console.WriteLine(s);
}
}
}
}

How would you suggest to in C# all users in GrpA and Grp B stored them in GrpAB using List<string>

This is my current solution. Any better search algorithms?
public void membersOfBothGroup(string groupA,string groupB)
{
List usersInGroupA = getGroupMembers(groupA);
List usersInGroupB = getGroupMembers(groupB);
List userInBothAB = new List();
foreach (string userA in usersInGroupA)
{
foreach(string userB in usersInGroupB)
{
if (userA == userB)
{
userInBothAB.Add(userA);
}
}
}
}

Here's an example (since the datatype is string):
List<string> groupA = new List<string>() { "Moe", "Larry", "Curly" };
List<string> groupB = new List<string>() { "Moe", "Shemp", "CurlyJoe" };
var result = groupB.Intersect(groupA);
Output:
Moe

How about:
List<string> userinBothAB = usersInGroupA.Intersect(usersInGroupB);
Check the MSDN for more details.