Develop Reference

fetch details from csv file on basis of name search c#

Step 1: I have created a C# application called : Student details
Step 2: Added four TextBoxes and named them as :
Image below to refer:
Studentname.Text
StudentSurname.Text
StudentCity.Text
StudentState.Text
DATA INSIDE CSV FILE
vikas,gadhi,mumbai,maharashtra
prem,yogi,kolkata,maha
roja,goal,orissa,oya
ram,kala,goa,barka
Issue is How do I fetch all the data(surname,city,state) of user prem into above textboxes studentsurname,studentcity,studentstate from csv file when I search the name in textbox 1 => studentname.Text as prem
Below is the Code where I am stuck at return null and code inside Load_Script_Click
void Connection_fetch_details(String searchName)
{
var strLines = File.ReadLines(filePath);
foreach (var line in strLines)
{
if (line.Split(',')[0].Equals(searchName))
{
Connection_fetch_details cd = new Connection_fetch_details()
{
username = line.Split(',')[1]
};
}
}
return;
}
private void Load_Script_Click(object sender, EventArgs e)
{
// load script is button
String con_env = textenv.Text.ToString();
//Address Address = GetAddress("vikas");
//textsurname.text = Address.Surname
Connection_fetch_details cd = Connection_fetch_details(con_env);
textusername.Text = cd.username;
}
==============================================================
Class file name : Address.class
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace DDL_SCRIPT_GENERATOR
{
public class Connection_fetch_details
{
public string username { get; set; }
}
}

The main problem is that your method is void, which means it doesn't return any value. So even though you may be finding a match, and creating a Connection_fetch_details object, you aren't returning that result back to the calling method.
This will fix that problem:
Connection_fetch_details Connection_fetch_details(String searchName)
{
var strLines = File.ReadLines(filePath);
foreach (var line in strLines)
{
if (line.Split(',')[0].Equals(searchName))
{
Connection_fetch_details cd = new Connection_fetch_details()
{
username = line.Split(',')[1]
};
return cd; //return the object containing the matched username
}
}
return null;
}
Now it will return a Connection_fetch_details object if there is a match, or null if there is no match.
Next, you asked about returning all the fields, not just one. For that you would need to
a) add more properties to your object
b) add more code to populate those properties from the CSV
c) add code to populate the textboxes with the results from the object.
I'm also going to rename "username" to something more relevant, since none of the field names you described in the question match that. I'm also going to rename your class to "Student", and rename your search method, for the same reason.
Here's an example:
Student searchStudent(String searchName)
{
var strLines = File.ReadLines(filePath);
foreach (var line in strLines)
{
var split = line.Split(',');
if (split[0].Equals(searchName))
{
Student s = new Student()
{
firstname = searchName,
surname = split[1],
city = split[2],
state = split[3]
};
return s; //return the object containing the matched name
}
}
return null;
}
private void Load_Script_Click(object sender, EventArgs e)
{
// load script is button
String con_env = textenv.Text.ToString();
//Address Address = GetAddress("vikas");
//textsurname.text = Address.Surname
Student st = searchStudent(con_env);
textsurname.Text = st.surname;
txtcity.Text = st.city;
txtstate.Text = st.state;
}
namespace DDL_SCRIPT_GENERATOR
{
public class Student
{
public string firstname { get; set; }
public string surname { get; set; }
public string city { get; set; }
public string state { get; set; }
}
}

To accomplish your goal you have to further separate your problem in more granular steps and also distinguish between what you show in your UI and what informations you hold in the background in which format.
Create a class with the desired properties
public class Student { public string Name { get; set; } ... }
Learn how to read a csv file into such an object by using an existing library like CsvHelper or CsvReader.
When you have something like List<Student> from this part. Learn how you can visualize such a thing by using some Binding (also depends on the visualization you use Winforms, WPF, etc.).
Depending on the visualization component it already supports filtering or you need to filter by yourself by using e.g. LINQ to get the matching elements students.Where(student => student.Name.StartsWith(search)).
So far a lot of smaller problems which is simply to much to answer in a single one. Please try to break down your problems into smaller ones and search for their solutions. If you get stuck, ask a new question. That's all I can do for you now.

Working with CSV file

I've been working and trying to solve this problem for maybe a whole week, which at this point I am wondering if I can solve it without it diving even deeper into the C# language, and I'm quite fairly new to C#, as well as working with CSV files and sorting and organizing them, so I'm fairly inexperienced into the whole spectrum of this.
I'm trying to sort a CSV file alphabetically, hide items that need to be hidden and have them have depth levels based on their parents, child and grandchild elements.
I've been successful with a couple of them, and written somewhat working code, but I don't know how to sort them alphabetically and give them the proper depth layer based on the parent and child they belong to.
Here's the mockup CSV that I've been trying to organize:
ID;MenuName;ParentID;isHidden;LinkURL
1;Company;NULL;False;/company
2;About Us;1;False;/company/aboutus
3;Mission;1;False;/company/mission
4;Team;2;False;/company/aboutus/team
5;Client 2;10;False;/references/client2
6;Client 1;10;False;/references/client1
7;Client 4;10;True;/references/client4
8;Client 5;10;True;/references/client5
10;References;NULL;False;/references
I've delimited the items by the semicolon, I've displayed the items that needs to be shown, but I fail to sort them like I should.
The sorting should look like this:
Company
About Us
Team
Mission
References
Client 1
Client 2
I've tried to sort them or display them in that order by getting the index of the slash, but what the code reproduces is not how it should be displayed, and, it looks like this:
Company
About Us
Mission
Team
Client 2
Client 1
References
In the other try, where I recursively match their parent id with the id, the console display looks like this:
Company
About Us
Mission
Team
Client 2
Client 1
References
I've tried solving this with a friend, and, even he doesn't know how to approach this problem, since this code should work on a different file that uses different parent ids.
On top of all this, I am unable to index them to an array, because there's only index of 0 or the index is based on their letters or crashes the console if I enter the index position of 1.
Here's the code for the first part where I fail to sort them:
class Program
{
static void Main(string[] args)
{
StreamReader sr = new StreamReader(#"Navigation.csv");
string data = sr.ReadLine();
while (data != null)
{
string[] rows = data.Split(';');
int id;
int parentId;
bool ids = Int32.TryParse(rows[0], out id);
string name = rows[1];
bool pIds = Int32.TryParse(rows[2], out parentId);
string isHidden = rows[3];
string linkUrl = rows[4];
string[] splitted = linkUrl.Split('/');
if (isHidden == "False")
{
List<CsvParentChild> pIdCid = new List<CsvParentChild>()
{
new CsvParentChild(id, parentId, name, linkUrl)
};
}
data = sr.ReadLine();
}
}
}
class CsvParentChild
{
public int Id;
public int ParentId;
public string Name;
public string LinkUrl;
public List<CsvParentChild> Children = new List<CsvParentChild>();
public CsvParentChild(int id, int parentId, string name, string linkUrl)
{
Id = id;
ParentId = parentId;
Name = name;
LinkUrl = linkUrl;
string[] splitted = linkUrl.Split(new char[] { '/' }, StringSplitOptions.RemoveEmptyEntries);
if (splitted.Length == 1)
{
Console.WriteLine($". { name }");
}
else if (splitted.Length == 2)
{
Console.WriteLine($".... { name }");
}
else if (splitted.Length == 3)
{
Console.WriteLine($"....... { name }");
}
}
}
And here's for the second part:
class Program
{
static void Main(string[] args)
{
// Get the path for the file
const string filePath = #"../../Navigation.csv";
// Read the file
StreamReader sr = new StreamReader(File.OpenRead(filePath));
string data = sr.ReadLine();
while (data != null)
{
string[] rows = data.Split(';');
ListItems lis = new ListItems();
int id;
int parentId;
// Get the rows/columns from the Csv file
bool ids = Int32.TryParse(rows[0], out id);
string name = rows[1];
bool parentIds = Int32.TryParse(rows[2], out parentId);
string isHidden = rows[3];
string linkUrl = rows[4];
// Split the linkUrl so that we get the position of the
// elements based on their slash
string [] splitted = linkUrl.Split(new char[] { '/' }, StringSplitOptions.RemoveEmptyEntries);
// If item.isHidden == "False"
// then display the all items whose state is set to false.
// If the item.isHidden == "True", then display the item
// whose state is set to true.
if (isHidden == "False")
{
// Set the items
ListItems.data = new List<ListItems>()
{
new ListItems() { Id = id, Name = name, ParentId = parentId },
};
// Make a new instance of ListItems()
ListItems listItems = new ListItems();
// Loop through the CSV data
for (var i = 0; i < data.Count(); i++)
{
if (splitted.Length == 1)
{
listItems.ListThroughItems(i, i);
}
else if (splitted.Length == 2)
{
listItems.ListThroughItems(i, i);
}
else
{
listItems.ListThroughItems(i, i);
}
}
}
// Break out of infinite loop
data = sr.ReadLine();
}
}
public class ListItems
{
public int Id { get; set; }
public string Name { get; set; }
public int ParentId { get; set; }
public static List<ListItems> data = null;
public List<ListItems> Children = new List<ListItems>();
// http://stackoverflow.com/a/36250045/7826856
public void ListThroughItems(int id, int level)
{
Id = id;
// Match the parent id with the id
List<ListItems> children = data
.Where(p => p.ParentId == id)
.ToList();
foreach (ListItems child in children)
{
string depth = new string('.', level * 4);
Console.WriteLine($".{ depth } { child.Name }");
ListThroughItems(child.Id, level + 1);
}
}
}
}

For each item, you need to construct a kind of "sort array" consisting of ids. The sort array consists of the ids of the item's ancestors in order from most distant to least distant. For "Team", our sort array is [1, 2, 4].
Here are the sort arrays of each item:
[1]
[1, 2]
[1, 3]
[1, 2, 4]
[10, 5]
[10, 6]
[10, 7]
[10, 8]
[10]
Once you have this, sorting the items is simple. When comparing two "sort arrays", start with the numbers in order in each array. If they are different, sort according to the value of the first number and you're done. If they are the same, look at the second number. If there is no second number, then sort by the length of the arrays, i.e., nothing comes before something.
Applying this algorithm, we get:
[1]
[1, 2]
[1, 2, 4]
[1, 3]
[10]
[10, 5]
[10, 6]
[10, 7]
[10, 8]
After that, hide the items based on the flag. I leave that to you because it's so simple. Depth is easy: It's the length of the sort array.

My Application was compiled and produced the following output with your data:
Company
About Us
Team
Mission
References
Client 1
Client 2
Client 4
Client 5
I would attempt to use object relation to create your tree like structure.
The main difficulty with the question is that parents don't matter. Children do.
So at some point in your code, you will need to reverse the hierarchy; Parsing Children first but reading their Parents first to create the output.
The roots of our tree are the data entries without parents.
Parsing
This should be pretty self explanatory, we have a nice class with a constructor that parses the input array and stores the data in it's properties.
We store all the rows in a list. After we are done with this, we pretty much converted the list, but no sorting happened at all.
public partial class csvRow
{
// Your Data
public int Id { get; private set; }
public string MenuName { get; private set; }
public int? ParentId { get; private set; }
public bool isHidden { get; private set; }
public string LinkURL { get; private set; }
public csvRow(string[] arr)
{
Id = Int32.Parse(arr[0]);
MenuName = arr[1];
//Parent Id can be null!
ParentId = ToNullableInt(arr[2]);
isHidden = bool.Parse(arr[3]);
LinkURL = arr[4];
}
private static int? ToNullableInt(string s)
{
int i;
if (int.TryParse(s, out i))
return i;
else
return null;
}
}
static void Main(string[] args)
{
List<csvRow> unsortedRows = new List<csvRow>();
// Read the file
const string filePath = #"Navigation.csv";
StreamReader sr = new StreamReader(File.OpenRead(filePath));
string data = sr.ReadLine();
//Read each line
while (data != null)
{
var dataSplit = data.Split(';');
//We need to avoid parsing the first line.
if (dataSplit[0] != "ID" )
{
csvRow lis = new csvRow(dataSplit);
unsortedRows.Add(lis);
}
// Break out of infinite loop
data = sr.ReadLine();
}
sr.Dispose();
//At this point we got our data in our List<csvRow> unsortedRows
//It's parsed nicely. But we still need to sort it.
//So let's get ourselves the root values. Those are the data entries that don't have a parent.
//Please Note that the main method continues afterwards.
Creating our Tree Strukture and Sorting the items
We start by defining Children and a public ChildrenSorted property that returns them sorted. That's actually allsorting we are doing, it's alot easier to sort than to work recursively.
We also need a function that add's children. It will pretty much filter the input and find all the rows where row.parentId = this.ID.
The last one is the function that defines our output and allows us to get something we can print into the console.
public partial class csvRow
{
private List<csvRow> children = new List<csvRow>();
public List<csvRow> ChildrenSorted
{
get
{
// This is a quite neet way of sorting, isn't it?
//Btw this is all the sorting we are doing, recursion for win!
return children.OrderBy(row => row.MenuName).ToList();
}
}
public void addChildrenFrom(List<csvRow> unsortedRows)
{
// Add's only rows where this is the parent.
this.children.AddRange(unsortedRows.Where(
//Avoid running into null errors
row => row.ParentId.HasValue &&
//Find actualy children
row.ParentId == this.Id &&
//Avoid adding a child twice. This shouldn't be a problem with your data,
//but why not be careful?
!this.children.Any(child => child.Id == row.Id)));
//And this is where the magic happens. We are doing this recursively.
foreach (csvRow child in this.children)
{
child.addChildrenFrom(unsortedRows);
}
}
//Depending on your use case this function should be replaced with something
//that actually makes sense for your business logic, it's an example on
//how to read from a recursiv structure.
public List<string> FamilyTree
{
get
{
List<string> myFamily = new List<string>();
myFamily.Add(this.MenuName);
//Merges the Trees with itself as root.
foreach (csvRow child in this.ChildrenSorted)
{
foreach (string familyMember in child.FamilyTree)
{
//Adds a tab for all children, grandchildren etc.
myFamily.Add("\t" + familyMember);
}
}
return myFamily;
}
}
}
Adding Items to the Tree and accessing them
This is the second part of my main function, where we actually work with our data (Right after sr.Dispose();)
var roots = unsortedRows.Where(row => row.ParentId.HasValue == false).
OrderBy(root => root.MenuName).ToList();
foreach (csvRow root in roots)
{
root.addChildrenFrom(unsortedRows);
}
foreach (csvRow root in roots)
{
foreach (string FamilyMember in root.FamilyTree)
{
Console.WriteLine(FamilyMember);
}
}
Console.Read();
}
Entire Sourcecode (Visual Studio C# Console Application)
You can use this to test, play around and learn more about recursive structures.
Copyright 2017 Eldar Kersebaum
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
using System;
using System.IO;
using System.Collections.Generic;
using System.Linq;
namespace ConsoleApplication49
{
class Program
{
static void Main(string[] args)
{
List<csvRow> unsortedRows = new List<csvRow>();
const string filePath = #"Navigation.csv";
StreamReader sr = new StreamReader(File.OpenRead(filePath));
string data = sr.ReadLine();
while (data != null)
{
var dataSplit = data.Split(';');
//We need to avoid parsing the first line.
if (dataSplit[0] != "ID" )
{
csvRow lis = new csvRow(dataSplit);
unsortedRows.Add(lis);
}
// Break out of infinite loop
data = sr.ReadLine();
}
sr.Dispose();
var roots = unsortedRows.Where(row => row.ParentId.HasValue == false).
OrderBy(root => root.MenuName).ToList();
foreach (csvRow root in roots)
{
root.addChildrenFrom(unsortedRows);
}
foreach (csvRow root in roots)
{
foreach (string FamilyMember in root.FamilyTree)
{
Console.WriteLine(FamilyMember);
}
}
Console.Read();
}
}
public partial class csvRow
{
// Your Data
public int Id { get; private set; }
public string MenuName { get; private set; }
public int? ParentId { get; private set; }
public bool isHidden { get; private set; }
public string LinkURL { get; private set; }
public csvRow(string[] arr)
{
Id = Int32.Parse(arr[0]);
MenuName = arr[1];
ParentId = ToNullableInt(arr[2]);
isHidden = bool.Parse(arr[3]);
LinkURL = arr[4];
}
private static int? ToNullableInt(string s)
{
int i;
if (int.TryParse(s, out i))
return i;
else
return null;
}
private List<csvRow> children = new List<csvRow>();
public List<csvRow> ChildrenSorted
{
get
{
return children.OrderBy(row => row.MenuName).ToList();
}
}
public void addChildrenFrom(List<csvRow> unsortedRows)
{
this.children.AddRange(unsortedRows.Where(
row => row.ParentId.HasValue &&
row.ParentId == this.Id &&
!this.children.Any(child => child.Id == row.Id)));
foreach (csvRow child in this.children)
{
child.addChildrenFrom(unsortedRows);
}
}
public List<string> FamilyTree
{
get
{
List<string> myFamily = new List<string>();
myFamily.Add(this.MenuName);
foreach (csvRow child in this.ChildrenSorted)
{
foreach (string familyMember in child.FamilyTree)
{
myFamily.Add("\t" + familyMember);
}
}
return myFamily;
}
}
}
}

Adding list to list and reading from it?

I have a problem where I need to store a List in another Class/List.
I have this class:
public class InformationMyTravels
{
public string MyTravelsDate { get; set; }
public string MyTravelsFromLocation { get; set; }
public string MyTravelsToLocation { get; set; }
}
And I can populate a List and then save it to my isolated storage (AppSettings).
The problem is that when I have more than one "Overview" below, then the following code will just append the travel history.
What I need is a separation of "Overview", so that the List I populate for each Overview is saved in another Class/List, which can contain the x-number of "Overview" lists I fetch.
private async Task Fetch()
{
AppSettings localStorage = new AppSettings();
List<InformationMyTravels> mytravelsreturned = new List<InformationMyTravels>();
// I need to separate the returned data per Overview
foreach (Overview loaded in localStorage.OverviewSetting)
{
string mytravelsHtml = await WebRequests.LoadPageAsyncSpecificRKMyTravels(loaded.CardOverviewID);
HtmlDocument htmlDocumentmytravels = new HtmlDocument();
htmlDocumentmytravels.LoadHtml(mytravelsHtml);
foreach (HtmlNode table in htmlDocumentmytravels.DocumentNode.SelectNodes("//table[#class='table']"))
{
foreach (HtmlNode row in table.SelectNodes("tr"))
{
InformationMyTravels newTravel = new InformationMyTravels();
newTravel.MyTravelsDate = row.SelectSingleNode("td[1]").InnerText.Trim();
newTravel.MyTravelsFromLocation = row.SelectSingleNode("td[3]").InnerText.Trim();
newTravel.MyTravelsToLocation = row.SelectSingleNode("td[5]").InnerText.Trim();
// Here it just appends with newTravel's
mytravelsreturned.Add(newTravel);
}
}
mytravelsreturned.Reverse();
}
localStorage.MyTravelsSetting = mytravelsreturned;
}
So how do I take "mytravelsreturned" and add this to another Class/List?
And afterwards I need to select the specific listindex from the new class and load the travels into a listbox.ItemsSource
Wanted hierarchy:
Class/List
InformationMyTravels (0)
MyTravelsDate(0)
MyTravelsFromLocation (0)
MyTravelsToLocation(0)
MyTravelsDate(1)
MyTravelsFromLocation (1)
MyTravelsToLocation(1)
etc.
InformationMyTravels (1)
MyTravelsDate(0)
MyTravelsFromLocation (0)
MyTravelsToLocation(0)
MyTravelsDate(1)
MyTravelsFromLocation (1)
MyTravelsToLocation(1)
etc.
I then need to load e.g InformationMyTravels (1) into a listbox.ItemsSource
I hope it makes sense.

Below is the untested code(I am not on Windows currently). It should give you the Idea.
Class InformationMyTravelsList<T> : List<T>
{
public int id{get; private set;}
public void AddInfo(int ID, InformationMyTravels info)
{
this.id = ID;
this.Add(info);
}
}
Class Main
{
void myLogic()
{
InformationMyTravels info = new InformationMyTravels();
InformationMyTravelsList<InformationMyTravels> infoList = new InformationMyTravelsList<InformationMyTravels>();
infoList.AddInfo(info); //add as many you want
List<InformationMyTravelsList<InformationMyTravels>> myList = new InformationMyTravelsList<InformationMyTravels>>();
myList.Add(infoList);
myListBox.DataSource = myList;
}
}

C# problem with object array

I am fairly new to arrays in C# and am used to storing a mass of data in a string and in INI files and then breaking it down into basic arrays using delimiters...so yeh, my knowledge is almost none existent.
My main form class begin this definition:
public CAirportData[] _AirportData; //size not known
This is the method I am using to create the array:
...string[] airports = possibleAirports.Split(','); //size is known
foreach (string airport in airports)
{
string[] rwys = inif.Read(airport, "rwys").Split(':'); //size is known (2)
_AirportData = new CAirportData[] { new CAirportData() { icao=airport, depRwy=rwys[0], arrRwy=rwys[1] } };
}
I know this just boils down to my limited knowledge of objects and arrays. But I can't seem to find anything on the internet that uses this sort of thing. I have tried to combine other peoples code with little success.
I need the _AirportData array to be available outside of the form hence public and declared outside of any methods. I supose the main problem is that I am overwriting array and foreach airport I am creating a new array hence loosing the previous. I had tried moving the ..= new CAirportData[] to all sorts of places but Visual Studio doesn't like it.
Below is the class definition for CAirportData:
public class CAirportData
{
public string icao { get; set; }
public string depRwy { get; set; }
public string arrRwy { get; set; }
public override string ToString()
{
string result = string.Format("ICAO: {0}, Dep: {1}, Arr: {2}", this.icao, this.depRwy, this.arrRwy);
return result;
}
}
public class CMRunways
{
public string icao { get; set; }
public string depRwy { get; set; }
public string arrRwy { get; set; }
}
Many thanks in advance for any help!

What you're looking for is generic List. Change the definition to:
public List<CAirportData> _AirportData = new List<CAirportData>();
Then the code in the loop to:
_AirportData.Add(new CAirportData { icao=airport, depRwy=rwys[0], arrRwy=rwys[1] });

This is what I would do...Create a static class, with a static property (airports) and add a static constructor to load the airports from file at the begining.
public static class Session
{
public static CAirportData[] _AirportData;
static Session()
{
string airports = possibleAirports.Split(",");
foreach (string airport in airports)
{
string[] rwys = inif.Read(airport, "rwys").Split(':'); //size is known (2)
_AirportData = new CAirportData[] { new CAirportData() { icao=airport, depRwy=rwys[0], arrRwy=rwys[1] } };
}
}
}
Now you can access the array anywhere in the project like
MessageBox.Show(Session.CAirportData[0].depRwy);

Create a object hierarchy from a list of folder locations

I have a list of locations as strings;
locA/locB
locA/locB/locH
locC/locD/locE
locC/locD/locE/locK
locF/locG
I've been trying to create an object that uses the same structure as the list of locations passed to it;
e.g. Something like..
var myHObject=CreateHeirarchicalObjectFromList(myStringListOfLocations);
I'm having problems looping through the list without almost doing it manually with loads of loops. Is there an easier way, maybe recursion?
I want to end up with an object like this;
.locA
.locB
.locH
.locC
.locD
.locE
.locK
.locF
.locG
That I can use to create a visual hierarchy.

Prob not the best but knocked up in LinqPad, will reformat in a sec..
void Main()
{
var strings = new string[]{"locA/locB","locA/locB/locH",
"locC/locD/locE","locC/locD/locE/locK","locF/locG"};
var folders = Folder.Parse(strings);
folders.Dump();
}
public class Folder
{
public string Name { get; set; }
public List<Folder> Folders { get; internal set; }
public Folder()
{
Folders = new List<Folder>();
}
//Presume that each string will be folder1/folder2/folder3
public static IEnumerable<Folder> Parse(IEnumerable<string> locations)
{
var folders = new List<Folder>();
foreach (string location in locations)
{
string[] parts = location.Split('/');
Folder current = null;
foreach (string part in parts)
{
var useFolders = current != null ?
current.Folders : folders;
current = useFolders.SingleOrDefault(f => f.Name == part) ?? new Folder() { Name = part };
if (!useFolders.Contains(current)) { useFolders.Add(current); }
}
}
return folders;
}
}