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Adding a new line in "string.join()" when formatting arrays?

Hello I am a newbie programmer, I am trying to format arrays in a way where there is a line break at the end of a specific set of arrays. I currently have 4 separate arrays in which I want to arrange each item in the array to a specific pattern. I have accomplished this task but now I am stumped because they are all in one line. Let me give you an example: (I am doing this on a datagridview by the way)
(This is what I want to happen)
Binder Clips Small pc 12 1260
Selleys All Clear pc 12 2400
(This is what I am getting)
Binder Clips Small pc 12 1260 Selleys All Clear pc 12 2400
This is my code:
//I get these from a datagridview
var items = carto.Rows
.Cast<DataGridViewRow>()
.Select(x => x.Cells[1].Value.ToString().Trim())
.ToArray();
var units = carto.Rows
.Cast<DataGridViewRow>()
.Select(x => x.Cells[2].Value.ToString().Trim())
.ToArray();
var quantity = carto.Rows
.Cast<DataGridViewRow>()
.Select(x => x.Cells[6].Value.ToString().Trim())
.ToArray();
var prices = carto.Rows
.Cast<DataGridViewRow>()
.Select(x => x.Cells[8].Value.ToString().Trim())
.ToArray();
//this is what I use to sort out the pattern that I want the arrays to be in
string[] concat = new string[items.Length * 4];
int index = 0;
for (int i = 0; i < items.Length; i++)
{
concat[index++] = items[i];
concat[index++] = units[i];
concat[index++] = quantity[i];
concat[index++] = prices[i];
}
// and this is where I am stuck because I can just put \n, it would ruin the format even more
cartitems.Text = string.Join(" ", concat);
I also tried doing something like this:
int j = 0;
string str = "";
foreach (var item in concat)
{
str += item;
if (j <= concat.Length - 1)
{
if (j % 3 == 0)
str += " ";
else
str += "\n";
}
j++;
}
It kinda gets the job done but the line breaks are all over the place.
This is what my projects look like so you can get a better gist on where am I getting the data from the 4 arrays:
basically the product name, unit, quantity and line total
and lastly I am storing in on a label so I can see how it the formatting looks like:
that about sums up my problem, I really hope you can help a newbie like me out, I have a feeling the answer is quite simple and I am just un-experienced.

As a general rule, you should keep your data structures (how the data is stored, implemented here as an array of values) separate from the data representation (in this case, written to a list box).
C# is an object-oriented language, so we might as well take advantage of that, right?
Create a class for your items.
class Item
{
public string Name { get; set; }
public string Unit { get; set; }
public string Quantity { get; set; }
public string Price { get; set; }
override public string ToString() {
return $"{Name} {Unit} {Quantity} {Price}";
}
}
This is how you load your array.
Item[] concat = new Item[items.Length];
int index = 0;
for (int i = 0; i < items.Length; i++) {
concat[index++] = new Item {
Name = items[i],
Unit = units[i],
Quantity = quantity[i],
Price = prices[i]
};
}
and this is how you can add the list of items to a listbox.
foreach(Item item in concat) {
listBox.Items.Add(item);
}

How to Split and Sum Members of a String Value

I have a database column that is a text field, and this text field contains values that look like
I=5212;A=97920;D=20181121|I=5176;A=77360;D=20181117|I=5087;A=43975;D=20181109
and can vary sometimes to look like:
I=29;A=20009.34;D=20190712;F=300|I=29;A=2259.34;D=20190714;F=300
Where 'I' represents the invoice Id, 'A' the invoice amount, 'D' the date in YYYYMMDD format and 'F' the original foreign currency value if the invoice was from a foreign supplier.
I am fetching that column and binding it to a datagrid which has a button labelled "Show Amount". On button click, it fetches the selected row and splits the string to extract "A"
I need to fetch all the sections with A= within the column result... i.e
A=97920
A=77360
A=43975
Then sum them all together and display the result on a label.
I have tried splitting using '|' first, extracting the substring 'A=' then splitting it using ';' to get the amount after "=".
string cAlloc;
string[] amount;
string InvoiceTotal;
string SupplierAmount;
string BalanceUnpaid;
DataRowView dv = invoicesDataGrid.SelectedItem as DataRowView;
if (dv != null)
{
cAlloc = dv.Row.ItemArray[7].ToString();
InvoiceTotal = dv.Row.ItemArray[6].ToString();
if (invoicesDataGrid.Columns[3].ToString() == "0")
{
lblAmount.Foreground = Brushes.Red;
lblAmount.Content = "No Amount Has Been Paid Out to the Supplier";
}
else
{
amount = cAlloc.Split('|');
foreach (string i in amount)
{
string toBeSearched = "A=";
string code = i.Substring(i.IndexOf(toBeSearched) + toBeSearched.Length);
string[] res = code.Split(';');
SupplierAmount = res[0];
float InvTotIncl = float.Parse(InvoiceTotal, CultureInfo.InvariantCulture.NumberFormat);
float AmountPaid = float.Parse(SupplierAmount, CultureInfo.InvariantCulture.NumberFormat);
float BalUnpaid = InvTotIncl - AmountPaid;
BalanceUnpaid = Convert.ToString(BalUnpaid);
if (BalUnpaid == 0)
{
lblAmount.Content = "Amount Paid = " + SupplierAmount + " No Balance Remaining, Supplier Invoice Paid in Full";
}
else if (BalUnpaid < 0)
{
lblAmount.Content = "Amount Paid = " + SupplierAmount + " Supplier Paid an Excess of " + BalanceUnpaid;
}
else
{
lblAmount.Content = "Amount Paid = " + SupplierAmount + " You Still Owe the Supplier a Total of " + BalanceUnpaid; ;
}
}
}
But I am only able to extract A=43975, the very last "A=". Instead of all three, plus I have not figured out how to sum the strings. Somebody help... please.

Regex is prefered solution. Alternatively split, split and split.
var cAlloc = "I=29;A=20009.34;D=20190712;F=300|I=29;A=2259.34;D=20190714;F=300";
var amount = cAlloc.Split('|');
decimal sum = 0;
foreach (string i in amount)
{
foreach (var t in i.Split(';'))
{
var p = t.Split('=');
if (p[0] == "A")
{
var s = decimal.Parse(p[1], CultureInfo.InvariantCulture);
sum += s;
break;
}
}
}

var in1 = "I=5212;A=97920;D=20181121|I=5176;A=77360;D=20181117|I=5087;A=43975;D=20181109";
var in2 = "I=29;A=20009.34;D=20190712;F=300|I=29;A=2259.34;D=20190714;F=300";
var reg = #"A=(\d+(\.\d+)?)";
Regex.Matches(in1, reg).OfType<Match>().Sum(m => double.Parse(m.Groups[1].Value));
Regex.Matches(in2, reg).OfType<Match>().Sum(m => double.Parse(m.Groups[1].Value));
You're doing too much work for something like this. Here's a simpler solution using Regex.

If the invoice amount is always located as a second value in the set you can access it directly by index after split:
var str = "I=5212;A=97920;D=20181121|I=5176;A=77360;D=20181117|I=5087;A=43975;D=20181109";
var invoices = str.Trim().Split(new[] { '|' }, StringSplitOptions.RemoveEmptyEntries);
var totalSum = 0M;
foreach (var invoice in invoices)
{
var invoiceParts = invoice.Split(new[] { ';' }, StringSplitOptions.RemoveEmptyEntries);
var invoiceAmount = decimal.Parse(invoiceParts[1].Trim().Substring(2));
totalSum += invoiceAmount;
}
Otherwise, you can use a little more "flexible" solution like this:
var str = "I=5212;A=97920;D=20181121|I=5176;A=77360;D=20181117|I=5087;A=43975;D=20181109";
var invoices = str.Trim().Split(new[] { '|' }, StringSplitOptions.RemoveEmptyEntries);
var totalSum = 0M;
foreach (var invoice in invoices)
{
var invoiceParts = invoice.Split(new[] { ';' }, StringSplitOptions.RemoveEmptyEntries);
var invoiceAmount = decimal.Parse(invoiceParts.First(ip => ip.Trim().ToLower().StartsWith("a=")).Substring(2));
totalSum += invoiceAmount;
}

Import the input: "Deserialisation"
With the following given input, we have a list of object with property name I,A, and D.
var input = "I=5212;A=97920;D=20181121|I=5176;A=77360;D=20181117|I=5087;A=43975;D=20181109";
Give this simple class:
public class inputClass
{
public decimal I { get; set; }
public decimal A { get; set; }
public decimal D { get; set; }
}
Parsing it will look like:
var inputItems =
input.Split('|')
.Select(
x =>
x.Split(';')
.ToDictionary(
y => y.Split('=')[0],
y => y.Split('=')[1]
)
)
.Select(
x => //Manual parsing from dictionary to inputClass.
//If dictionary Key match an object property we could use something more generik.
new inputClass
{
I = decimal.Parse(x["I"], CultureInfo.InvariantCulture.NumberFormat),
A = decimal.Parse(x["A"], CultureInfo.InvariantCulture.NumberFormat),
D = decimal.Parse(x["D"], CultureInfo.InvariantCulture.NumberFormat),
}
)
.ToList();
It look complexe? lets give the inputClass the responsability to initialise it self based on string
PropertyName=Value[; PropertyName=Value] :
public inputClass(string input, NumberFormatInfo numberFormat)
{
var dict = input
.Split(';')
.ToDictionary(
y => y.Split('=')[0],
y => y.Split('=')[1]
);
I = decimal.Parse(dict["I"], numberFormat);
A = decimal.Parse(dict["A"], numberFormat);
D = decimal.Parse(dict["D"], numberFormat);
}
Then the parsing is simple:
var inputItems = input.Split('|').Select(x => new inputClass(x, CultureInfo.InvariantCulture.NumberFormat));
Once we have a more useable Structure a List of object We can easly compute Sum, Avg, Max, Min:
var sumA = inputItems.Sum(x => x.A);
Producing the output: "Serialisation"
In order to process the input we will define an object like similar to the Input
public class outputClass
{
public decimal I { get; set; }
public decimal A { get; set; }
public decimal D { get; set; }
public decimal F { get; set; }
The Class should be able to produce the String PropertyName=Value[; PropertyName=Value], :
public override string ToString()
{
return $"I={I};A={A};D={D};F={F}";
}
Then producing and string "serialisation" after computing the ListOutput based on the List input:
//process The input into the output.
var outputItems = new List<outputClass>();
foreach (var item in inputItems)
{
// compute things to be able to create the nex output item
item.A++;
outputItems.Add(
new outputClass { A = item.A, D = item.D, I = item.I, F = 42 }
);
}
// "Serialisation"
var outputString = String.Join("|", outputItems);
Online Demo. https://dotnetfiddle.net/VcEQmf
Long story short:
Define a class with the property you will use/display.
Add a constructor that take a string like "I=5212;A=97920;D=20181121"
nb: the String may contain property that will not be map to the object
Override the ToString(), so It can easly produce it's serialisation.
nb: Property and value that are not stored in the object will not be in the serialisation result.
Now You simply have to split on your line/object separator "|" and you are ready to go using real object, not having to care about that weird string anymore.
PS:
There was a little missunderstand about your 2 type of inputs, I mentally saw them as input, output. Dont mind those name. It can be the same class. It doens't change anything in this answer.

Sort a List in which each element contains 2 Values

I have a text file that contains Values in this Format: Time|ID:
180|1
60 |2
120|3
Now I want to sort them by Time. The Output also should be:
60 |2
120|3
180|1
How can I solve this problem? With this:
var path = #"C:\Users\admin\Desktop\test.txt";
List<string> list = File.ReadAllLines(path).ToList();
list.Sort();
for (var i = 0; i < list.Count; i++)
{
Console.WriteLine(list[i]);
}
I got no success ...

3 steps are necessary to do the job:
1) split by the separator
2) convert to int because in a string comparison a 6 comes after a 1 or 10
3) use OrderBy to sort your collection
Here is a linq solution in one line doing all 3 steps:
list = list.OrderBy(x => Convert.ToInt32(x.Split('|')[0])).ToList();
Explanation
x => lambda expression, x denotes a single element in your list
x.Split('|')[0] splits each string and takes only the first part of it (time)
Convert.ToInt32(.. converts the time into a number so that the ordering will be done in the way you desire
list.OrderBy( sorts your collection
EDIT:
Just to understand why you got the result in the first place here is an example of comparison of numbers in string representation using the CompareTo method:
int res = "6".CompareTo("10");
res will have the value of 1 (meaning that 6 is larger than 10 or 6 follows 10)
According to the documentation->remarks:
The CompareTo method was designed primarily for use in sorting or alphabetizing operations.

You should parse each line of the file content and get values as numbers.
string[] lines = File.ReadAllLines("path");
// ID, time
var dict = new Dictionary<int, int>();
// Processing each line of the file content
foreach (var line in lines)
{
string[] splitted = line.Split('|');
int time = Convert.ToInt32(splitted[0]);
int ID = Convert.ToInt32(splitted[1]);
// Key = ID, Value = Time
dict.Add(ID, time);
}
var orderedListByID = dict.OrderBy(x => x.Key).ToList();
var orderedListByTime = dict.OrderBy(x => x.Value).ToList();
Note that I use your ID reference as Key of dictionary assuming that ID should be unique.
Short code version
// Key = ID Value = Time
var orderedListByID = lines.Select(x => x.Split('|')).ToDictionary(x => Convert.ToInt32(x[1]), x => Convert.ToInt32(x[0])).OrderBy(x => x.Key).ToList();
var orderedListByTime = lines.Select(x => x.Split('|')).ToDictionary(x => Convert.ToInt32(x[1]), x => Convert.ToInt32(x[0])).OrderBy(x => x.Value).ToList();

You need to convert them to numbers first. Sorting by string won't give you meaningful results.
times = list.Select(l => l.Split('|')[0]).Select(Int32.Parse);
ids = list.Select(l => l.Split('|')[1]).Select(Int32.Parse);
pairs = times.Zip(ids, (t, id) => new{Time = t, Id = id})
.OrderBy(x => x.Time)
.ToList();

Thank you all, this is my Solution:
var path = #"C:\Users\admin\Desktop\test.txt";
List<string> list = File.ReadAllLines(path).ToList();
list = list.OrderBy(x => Convert.ToInt32(x.Split('|')[0])).ToList();
for(var i = 0; i < list.Count; i++)
{
Console.WriteLine(list[i]);
}

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class TestClass {
public static void main(String[] args) {
List <LineItem> myList = new ArrayList<LineItem>();
myList.add(LineItem.getLineItem(500, 30));
myList.add(LineItem.getLineItem(300, 20));
myList.add(LineItem.getLineItem(900, 100));
System.out.println(myList);
Collections.sort(myList);
System.out.println("list after sort");
System.out.println(myList);
}
}
class LineItem implements Comparable<LineItem>{
int time;
int id ;
#Override
public String toString() {
return ""+ time + "|"+ id + " ";
}
#Override
public int compareTo(LineItem o) {
return this.time-o.time;
}
public static LineItem getLineItem( int time, int id ){
LineItem l = new LineItem();
l.time=time;
l.id=id;
return l;
}
}

How to perform word search using LINQ?

I have a list which contains the name of suppliers. Say
SuppId Supplier Name
----------------------------------
1 Aardema & Whitelaw
2 Aafedt Forde Gray
3 Whitelaw & Sears-Ewald
using following LINQ query
supplierListQuery = supplierListQuery.Where(x => x.SupplierName.Contains(SearchKey));
I can return records correctly in the following conditions,
1) If i am using search string as "Whitelaw & Sears-Ewald" it will return 3rd record.
2) If i am using "Whitelaw" or "Sears-Ewald" it will return 3rd record.
But how can i return 3rd record if i am giving search string as "Whitelaw Sears-Ewald". It always returns 0 records.
Can i use ALL to get this result, but i dont know how to use it for this particular need.

What I usually do in this situation is split the words into a collection, then perform the following:
var searchopts = SearchKey.Split(' ').ToList();
supplierListQuery = supplierListQuery
.Where(x => searchopts.Any(y=> x.SupplierName.Contains(y)));

This works for me:
IEnumerable<string> keyWords = SearchKey.Split('');
supplierListQuery = supplierListQuery
.AsParallel()
.Where
(
x => keyWords.All
(
keyword => x.SupplierName.ContainsIgnoreCase(keyword)
)
);

Thank you all for your quick responses. But the one which worked or a easy fix to handle this was timothyclifford's note on this. Like he said i alterd my answer to this
string[] filters = SearchKey.ToLower().Split(new[] { ' ' });
objSuppliersList = (from x in objSuppliersList
where filters.All(f => x.SupplierName.ToLower().Contains(f))
select x).ToList();
Now it returns the result for all my serach conditions.

Because "Whitelaw" appears in both you will get both records. Otherwise there is no dynamic way to determine you only want the last one. If you know you only have these 3 then append .Last() to get the final record.
supplierListQuery = supplierListQuery.Where(x => x.SupplierName.Contains(SearchKey.Split(' ')[0]));

You need to use some sort of string comparer to create your own simple Search Engine and then you can find strings that are most likely to be included in your result :
public static class SearchEngine
{
public static double CompareStrings(string val1, string val2)
{
if ((val1.Length == 0) || (val2.Length == 0)) return 0;
if (val1 == val2) return 100;
double maxLength = Math.Max(val1.Length, val2.Length);
double minLength = Math.Min(val1.Length, val2.Length);
int charIndex = 0;
for (int i = 0; i < minLength; i++) { if (val1.Contains(val2[i])) charIndex++; }
return Math.Round(charIndex / maxLength * 100);
}
public static List<string> Search(this string[] values, string searchKey, double threshold)
{
List<string> result = new List<string>();
for (int i = 0; i < values.Length; i++) if (CompareStrings(values[i], searchKey) > threshold) result.Add(values[i]);
return result;
}
}
Example of usage :
string[] array = { "Aardema & Whitelaw", "Aafedt Forde Gray", "Whitelaw & Sears-Ewald" };
var result = array.Search("WhitelawSears-Ewald", 80);
// Results that matches this string with 80% or more
foreach (var item in result)
{
Console.WriteLine(item);
}
Output: Whitelaw & Sears-Ewald

If you want an easy (not very handy) solution,
var result = supplierListQuery
.Select(x => normalize(x.SupplierName))
.Where(x => x.Contains(normalize(SearchKey)));
string normalize(string inputStr)
{
string retVal = inputStr.Replace("&", "");
while (retVal.IndexOf(" ") >= 0)
{
retVal = retVal.Replace(" ", " ");
}
return retVal;
}

Most efficient way to make duplicates unique in collection

I have a collection. And in this collection, if a duplicate is added, I want to append the text " - N" (Where N is an integer that is not used by a current item in the collection).
For Example, if I have the following list:
item1
item2
and try to add 'item1' again, I want the list to end up like so:
item1
item2
item1 - 1
If I try to add 'item1' again, the list will then be:
item1
item2
item1 - 1
item1 - 2
Pretty straight forward. Below is my simple algorithm, but I'm getting a noticeable loss in performance when dealing with 10,000 items. Obviously that's going to happen somewhat, but are there better approaches to this? Couldn't find any similar question asked, so figure I'd see if anyone has ran into a similar issue.
Item copyItem = new Item();
string tempName = name;
int copyNumber = 1;
while(copyItem != null)
{
copyItem = MyCollection.FirstOrDefault(blah => blah.Name == tempName);
if (copyItem == null)
{
name = tempName;
break;
}
tempName = name + " - " + copyNumber;
++copyNumber;
}

I would firstly sort the values - thanks to this you only need to make a check with the previous value and not with the whole collection.
So it could look like this:
List<string> values = new List<string> { "item1", "item1", "item1" };
values.Sort();
string previousValue = string.Empty;
int number = 1;
for(int i = 0 ; i < values.Count; i ++)
{
if (values[i].Equals(previousValue))
{
previousValue = values[i];
values[i] = values[i] + "-" + number;
number++;
}
else
{
previousValue = values[i];
number = 1;
}
}

I would use a Dictionary<string, int> to store the number of duplicates for a particular item. So a helper method would look something like this:
Dictionary<string, int> countDictionary = new Dictionary<string, int>(); // case sensitive!
string GetNameForItem(string itemName)
{
var name = itemName;
var count = 0;
countDictionary.TryGetValue(itemName, out count);
if (count > 0)
name = string.Format("{0} - {1}", itemName, count);
countDictionary[itemName] = count + 1;
return name;
}
Alternatively, you could split up the operation into several methods if you didn't want GetNameForItem to automatically increment on retrieval:
int GetCountForItem(string itemName)
{
var count = 0;
countDictionary.TryGetValue(itemName, out count);
return count;
}
string GetNameForItem(string itemName)
{
var name = itemName;
var count = GetCountForItem(itemName);
if (count > 0)
name = string.Format("{0} - {1}", itemName, count);
return name;
}
int IncrementCountForItem(string itemName)
{
var newCount = GetCountForItem(itemName) + 1;
countDictionary[itemName] = newCount;
return newCount;
}
It is important to note that if you are supporting deletion from the collection, you will have to update the count accordingly:
int DecrementCountForItem(string itemName)
{
var newCount = Math.Max(0, GetCountForItem(itemName) - 1); // Prevent count from going negative!
countDictionary[itemName] = newCount;
return newCount;
}
You will also have to keep in mind what happens if you have two items, say "Item A" and "Item A - 1", then you delete "Item A". Should you rename "Item A - 1" to "Item A"?

Okay so you need an iterator per value and not a global one. This code will do the thing.
// Inputs for Tests purpose
List<string> values = new List<string> { "item1", "item2", "item1", "item1" };
// Result data
List<string> finalResult = new List<string>();
// 1 - Group by item value
var tempResult = from i in values
group i by i;
// We loop over all different item name
foreach (var curItem in tempResult)
{
// Thanks to the group by we know how many item with the same name exists
for (int ite = 0; ite < curItem.Count(); ite++)
{
if (ite == 0)
finalResult.Add(curItem.Key);
else
finalResult.Add(string.Format("{0} - {1}", curItem.Key, ite));
}
}
Thanks to LINQ you can reduce the amount of code, next code will do exactly the same thing and should be also quickier because I use the ToList() method so the LINQ query will not have a deferred execution.
// Inputs for Tests purpose
List<string> values = new List<string> { "item1", "item2", "item1", "item1" };
// Result data
List<string> finalResult = new List<string>();
values.GroupBy<string, string>(s1 => s1).ToList().ForEach(curItem =>
{
for (int ite = 0; ite < curItem.Count(); ite++)
{
finalResult.Add(ite == 0 ? curItem.Key : string.Format("{0} - {1}", curItem.Key, ite));
}
});