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Using Regex Array with String Array

I'm trying to make a program where a user can input an array of serial numbers and have each corresponding product show up.
Suppose I know that Product A always starts with "C02", Product B always ends in "X02", and Product C always contains "A1700". Then if the user input was "C02HGV32,N93XA1700D,J3429X02", it would return "C02HGV32: Product A; N93XA1700D: Product C; J3429X02: Product B".
How would I get an array of Regex expressions to compare against the array of strings? Here's what I have:
using System.Text.RegularExpressions;
public class ReturnProduct{
public Regex[] compareAgainst = new Regex[3]{#"[C02]*",#"*[X02]",#"*[A1700]*"}; //Clearly not the right way, but not sure how else to do it
...
public string getTheProduct(string input){
string[] compareString = input.Split(",");
for (int a = 0; a < compareString.Length; a++){
for (int b = 0; b < compareAgainst.Length; b++){
//Do something Regex-y with compareString[a] and compareAgainst[b]
}
}

If the requirements of these codes are so simple you can use String.Contains, String.StartsWith and String.EndsWith. You can create a Dictionary to hold product names and functions to check if a given string has the pattern for a product.
var dict = new Dictionary<string, Predicate<string>>
{
["Product A"] = s => s.StartsWith("C02"),
["Product B"] = s => s.EndsWith("X02"),
["Product C"] = s => s.Contains("A1700")
};
string GetProductName(string serialNum)
{
foreach(var keyVal in dict)
{
if(keyVal.Value(serialNum))
return keyVal.Key;
}
return "No product name found";
}
List<(string, string)> GetProductNames(string str)
{
var productCodes = str.Split(',');
var productNames = new List<(string, string)>(); // list of tuples (string, string)
foreach(var serialNum in productCodes)
{
productNames.Add((serialNum, GetProductName(serialNum)));
}
return productNames;
}
Usage:
var userString = "C02HGV32,N93XA1700D,J3429X02";
List<(string serialNum, string name)> productNames = GetProductNames(userString);
foreach(var tuple in productNames)
{
Console.WriteLine($"{tuple.serialNum} : {tuple.name}");
}
If you specifically want to use Regex, you can use the following patterns:
var regexDict = new Dictionary<string, Regex>
{
["Product A"] = new Regex("^C02"), //'^' means beginning of string
["Product B"] = new Regex("X02$"), //'$' means end of string
["Product C"] = new Regex("A1700") //given string anywhere
};
string GetProductName(string serialNum)
{
foreach(var keyVal in regexDict)
{
if(keyVal.Value.IsMatch(serialNum))
return keyVal.Key;
}
return "No product name found";
}
List<(string, string)> GetProductNames(string str)
{
var productCodes = str.Split(',');
var productNames = new List<string>();
foreach(var serialNum in productCodes)
{
productNames.Add((serialNum, GetProductName(serialNum)));
}
return productNames;
}

Define a class for your products:
public class Product
{
public string Name { get; set; }
public Regex Expr { get; set; }
}
then create an array with all your regexes:
var regexes = new[]
{
new Product
{
Name = "Product A",
Expr = new Regex("^C02")
},
new Product
{
Name = "Product B",
Expr = new Regex("X02$")
},
new Product
{
Name = "Product C",
Expr = new Regex("A1700")
}
};
now you can use LINQ query:
var input = "C02HGV32,N93XA1700D,J3429X02";
var result = string.Join("; ",
input.Split(',')
.Select(s => new {regexes.FirstOrDefault(p => p.Expr.IsMatch(s))?.Name, Value = s})
.Select(x => $"{x.Value}: {x.Name}"));
result would be
C02HGV32: Product A; N93XA1700D: Product C; J3429X02: Product B

Regex syntax:
"^C02.*" - Starts with C02 followed by any number of characters including 0 characters.
"^.*X02" - Starts with any number of characters including 0 characters and ends with X02.
"^.A1700.*" - Starts and ends with any number of characters, and contains A1700 somewhere.
public static void GetTheProduct(string input, List<Regex> regList)
{
List<string> compareString = input.Split(new char[] { ',' }).ToList();
foreach (string item in compareString)
{
if (regList[0].Match(item).Success)
Console.WriteLine("{0} : {1}", item, "Product A");
else if (regList[1].Match(item).Success)
Console.WriteLine("{0} : {1}", item, "Product B");
else if (regList[2].Match(item).Success)
Console.WriteLine("{0} : {1}", item, "Product C");
}
}
static void Main(string[] args)
{
List<Regex> regexList = new List<Regex>() { new Regex("^C02.*"), new Regex("^.*X02"), new Regex("^.*A1700.*") };
GetTheProduct("C02HGV32,N93XA1700D,J3429X02", regexList);
Console.ReadLine();
}
You could also generalize the method and avoid hardcoding Product names.
Like so:
public static void GetTheProduct(string input, Dictionary<string, Regex> regDictionary)
{
List<string> compareString = input.Split(new char[] { ',' }).ToList();
foreach (string item in compareString)
{
string key = regDictionary.First(x => x.Value.IsMatch(item)).Key;
Console.WriteLine("{0} : {1}", item, key);
}
}
static void Main(string[] args)
{
Dictionary<string, Regex> regDictionary = new Dictionary<string, Regex>();
regDictionary.Add("Product A", new Regex("^C02.*"));
regDictionary.Add("Product B", new Regex("^.*X02"));
regDictionary.Add("Product C", new Regex("^.*A1700.*"));
GetTheProduct("C02HGV32,N93XA1700D,J3429X02", regDictionary);
Console.ReadLine();
}

Linq query to take the value from Array with matching sub string value

I have a string - filterArg and array of string - arrayColDef as shown in below code. I am trying to split the string filterArg by |~| and trying to get the value from filterArg by matching arrayColDef value.
Can any one let me know how to get the value ToDo commented in the code
static void Main(string[] args)
{
Hashtable ht = new Hashtable();
string filterArg = "ZipCode=2130|~|ZipPlace=KNAPPER";
string[] arrayColDef = { "ZipCode", "Space", "ZipPlace" };
foreach (var item in arrayColDef)
{
var key = item;
var value = filterArg.Split(new string[] { "|~|" }, StringSplitOptions.RemoveEmptyEntries);//TODO: here value should hold = 2130 for first itteration
ht.Add(item, value);
}
}

I think you get complicated iterating over arrayColDef, it's easier to iterate through splited string and extract the values.
You can do something like below.
static void Main(string[] args)
{
Hashtable ht = new Hashtable();
string filterArg = "ZipCode=2130|~|ZipPlace=KNAPPER";
string[] arrayColDef = { "ZipCode", "Space", "ZipPlace" };
var properties = filterArg.Split(new string[] { "|~|" }, StringSplitOptions.RemoveEmptyEntries);
foreach (var property in properties)
{
var nameValue = property.Split(arrayColDef, StringSplitOptions.RemoveEmptyEntries);
var item = property.Split('=').First(); // get key
var value = nameValue.First().TrimStart('='); // get value
ht.Add(item, value);
}
}

Hashtable ht = new Hashtable();
string filterArg = "ZipCode=2130|~|ZipPlace=KNAPPER";
string[] arrayColDef = { "ZipCode", "Space", "ZipPlace" };
var filterArr = filterArg.Split(new string[] { "|~|" }, StringSplitOptions.RemoveEmptyEntries)
.Select(x => x.Split('='));
foreach (var item in arrayColDef)
{
var key = item;
var v = filterArr.FirstOrDefault(x => x[0] == item);
if (v != null&&v.Length>1)
{
ht.Add(item, v[1]);
}
}
foreach (var key in ht.Keys)
{
Console.WriteLine("Key:{0} Value:{1}", key, ht[key]);
}
Space has been ignored

The filter split in
var value = filterArg.Split(new string[] { "|~|" }, StringSplitOptions.RemoveEmptyEntries);//TODO: here value should hold = 2130 for first itteration
returns an array. You can get the final value by filtering and replacing with linq:
string finalValue = value.Where(m => m.Contains(item)).Select(m => m.Replace(item+"=","")).FirstOrDefault();
The value, then, is in finalValue variable.
Greetings

Error Cannot implicitly convert type 'string[]' to 'string'

I am experiencing an Error within nouns[i] = SearchKeywords(words, sentences); every time I run my program. What should I do?
*I edited to include the SearchKeywords method. I am trying to find all words that have "a" and "an" before them.
Error is,
Error Cannot implicitly convert type 'string[]' to 'string'
string[] SearchKeywords(List<string> keywords, string[] sentence){
int[] location = new int[sentence.Length];
foreach (string word in keywords)
{
for (int i = 0; i < sentence.Length;i++ )
{
string[] nouns = new string[i];
if (String.IsNullOrEmpty(sentence[i]))
{
return null;
}
else
{
location[i] = sentence[i].IndexOf(word);
nouns[i] = sentence[i].Substring(location[i]);
if (nouns[i].Contains(word)) return nouns;
}
}
}
return sentence;
string[] checkForIndefinite()
{
string input = txtEntry.Text;
string text = lbltxtOutput.Text;
Tools tool = new Tools();
List<string> words = new List<string>();
words.Add("an");
words.Add("a");
foreach(string sentence in GetWords(text))
{
for (int i = 0; i < sentence.Length; i++)
{
string[] nouns = new string[i];
string[] sentences = new string[i];
sentences[i] = sentence;
**nouns[i] = SearchKeywords(words, sentences);**
return nouns;
}
}
return null;
}

It seems to me that this is what you need:
string[] SearchKeywords(List<string> keywords, string[] sentence)
{
return
sentence
.Zip(sentence.Skip(1), (w0, w1) => new { w0, w1 })
.Where(ww => keywords.Contains(ww.w0))
.Select(ww => ww.w1)
.ToArray();
}
string[] checkForIndefinite()
{
var input = txtEntry.Text;
var text = lbltxtOutput.Text;
var words = new List<string>() { "an", "a" };
return SearchKeywords(words, GetWords(text));
}

The output of the SearchKeywords function is an string[] and the nouns[i] is a string and simply you cannot assign and string[] value to a string. So You may what to try something like this:
List<string> nouns = new List<string>();
//foreach loop
// for loop
nouns.AddRange(SearchKeywords(words, sentences));

using System;
using System.Security.Cryptography;
using System.Text;
using System.Collections.Generic;
public class Program
{
public static void Main()
{
string[] indefinites = checkForIndefinite();
foreach (string s in indefinites)
{
Console.WriteLine(s);
}
}
static string[] SearchKeywords(List<string> keywords, string sentence)
{
if (String.IsNullOrEmpty(sentence))
{
return null;
}
List<string> nouns = new List<string>();
string[] words = sentence.Split(' ');
foreach (string keyword in keywords)
{
for (int i = 0; i < words.Length; i++ )
{
if (words[i] == keyword)
{
if (i+1 < words.Length && !nouns.Contains(words[i+1]))
{
nouns.Add(words[i+1]);
}
}
}
}
return nouns.ToArray();
}
static string[] checkForIndefinite()
{
string sentence = "This is not an interesting sentence to use to test a program";
string text = string.Empty;
List<string> words = new List<string>();
words.Add("an");
words.Add("a");
return SearchKeywords(words, sentence);
}
}
This compiles and returns the following:
interesting
program

Connect element in distinct array using recursion

if I have two array
A:[A,B]
B:[1,2,3]
how can I create a string List like [A_1, A_2, A_3, B_1, B_2, B_3]
the number of array is not regular, it's maybe have 3 more
A:[A,B]
B:[1,2,3]
C:[w,x,y,z]
D:[m,n]
E:[p,q,r]
can I use recursive to solve it?

So, we define a functions Mergethat takes lists of list of stings and merges them into the string enumerable you want
static void Main(string[] args)
{
var a = new[] { "A", "B" };
var b = new[] { "1", "2", "3" };
var c = new[] { "x", "y", "z", "w" };
var result = Merge(a, b, c);
foreach (var r in result)
{
Console.WriteLine(r);
}
}
public static IList<string> Merge(params IEnumerable<string>[] lists)
{
return Merge((IEnumerable<IEnumerable<string>>) lists);
}
public static IList<string> Merge(IEnumerable<IEnumerable<string>> lists)
{
var retval = new List<string>();
var first = lists.FirstOrDefault();
if (first != null)
{
var result = Merge(lists.Skip(1));
if (result.Count > 0)
{
foreach (var x in first)
{
retval.AddRange(result.Select(y => string.Format("{0}_{1}", x, y)));
}
}
else
{
retval.AddRange(first);
}
}
return retval;
}
we can also improve this, if you use Lists as inputs
public static IList<string> Merge(params IList<string>[] lists)
{
return Merge((IList<IList<string>>) lists);
}
public static IList<string> Merge(IList<IList<string>> lists, int offset = 0)
{
if (offset >= lists.Count)
return new List<string>();
var current = lists[offset];
if (offset + 1 == lists.Count) // last entry in lists
return current;
var retval = new List<string>();
var merged = Merge(lists, offset + 1);
foreach (var x in current)
{
retval.AddRange(merged.Select(y => string.Format("{0}_{1}", x, y)));
}
return retval;
}

This is simple iterating over n-ary dimension - no need for recursion for that, just array to store indexes.
static void Iterate(int[] iterators, ArrayList[] arrays) {
for (var j = iterators.Length - 1; j >= 0; j--) {
iterators[j]++;
if (iterators[j] == arrays[j].Count) {
if (j == 0) {
break;
}
iterators[j] = 0;
} else {
break;
}
}
}
static IList<string> Merge(ArrayList[] arrays) {
List<string> result = new List<string>();
int[] iterators = new int[arrays.Length];
while (iterators[0] != arrays[0].Count) {
var builder = new StringBuilder(20);
for(var index = 0; index < arrays.Length; index++) {
if (index > 0) {
builder.Append("_");
}
builder.Append(arrays[index][iterators[index]]);
}
result.Add(builder.ToString());
Iterate(iterators, arrays);
}
return result;
}
static void Main(string[] args) {
var list1 = new ArrayList();
var list2 = new ArrayList();
var list3 = new ArrayList();
list1.Add(1);
list1.Add(2);
list2.Add("a");
list2.Add("b");
list3.Add("x");
list3.Add("y");
list3.Add("z");
var result = Merge(new[] { list1, list2, list3 });
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace arrconn {
class Program {
static string[] conn(params Array[] arrs) {
if(arrs.Length == 0) return new string[0];
if(arrs.Length == 1) {
string[] result = new string[arrs[0].Length];
for(int i = 0; i < result.Length; i++)
result[i] = arrs[0].GetValue(i).ToString();
return result; }
else {
string[] result = new string[arrs[0].Length*arrs[1].Length];
for(int i = 0; i < arrs[0].Length; i++)
for(int j = 0; j < arrs[1].Length; j++)
result[i*arrs[1].Length+j] = string.Format("{0}_{1}", arrs[0].GetValue(i), arrs[1].GetValue(j));
if(arrs.Length == 2) return result;
Array[] next = new Array[arrs.Length-1];
next[0] = result; Array.Copy(arrs, 2, next, 1, next.Length-1);
return conn(next);
}
}
static void Main(string[] args) {
foreach(string s in conn(
new string[] { "A", "B" },
new int[] { 1, 2, 3 },
new string[] { "x" },
new string[] { "$", "%", "#" }))
Console.WriteLine(s);
Console.Read();
}
}
}

I guess your input are like this:
var A = ["A","B"];
var B = [1,2,3];
var C = ["x","y","z","w"];
And what you want to obtain is:
var result = ["A_1_x", "A_1_y",...
"A_2_x", "A_2_y",...
"A_3_x", "A_3_y",...
"B_1_x", "B_1_y",...
...
..., "B_3_z", "B_3_w"];
We'll be working with IEnumerable as it will simplify the work for us and give us access to the yield keyword.
First, let's take care of the case where we only concataining two collections:
IEnumerable<string> ConcatEnumerables(IEnumerable<object> first, IEnumerable<object> second)
{
foreach (var x in first)
{
foreach (var y in second)
{
yield return x.ToString() + "_" + y.ToString();
}
}
}
Then we can recursively takle any number of collections:
IEnumerable<string> ConcatEnumerablesRec(IEnumerable<IEnumerable<object>> enums)
{
//base cases
if(!enums.Any())
{
return Enumerable.Empty<string>();
}
if (enums.Count() == 1)
{
return enums.First().Select(o => o.ToString());
}
//recursively solve the problem
return ConcatEnumerables(enums.First(), ConcatEnumerablesRec(enums.Skip(1));
}
Now you just need to call ToArray on the result if you really need an array as your output.
string[] Concatenator(params object[][] parameters)
{
return ConcatEnumerablesRec(parameters).ToArray();
}

This should do the trick. Note that the input sequences do not have to be arrays - they can be any type that implements IEnumerable<>.
Also note that we have to case sequences of value types to sequences of <object> so that they are assignable to IEnumerable<object>.
Here's the compilable Console app demo code:
using System;
using System.Collections.Generic;
using System.Linq;
namespace Demo
{
internal static class Program
{
static void Main()
{
string[] a = {"A", "B", "C", "D"};
var b = Enumerable.Range(1, 3); // <-- See how it doesn't need to be an array.
char[] c = {'X', 'Y', 'Z'};
double[] d = {-0.1, -0.2};
var sequences = new [] { a, b.Cast<object>(), c.Cast<object>(), d.Cast<object>() };
Console.WriteLine(string.Join("\n", Combine("", sequences)));
}
public static IEnumerable<string> Combine(string prefix, IEnumerable<IEnumerable<object>> sequences)
{
foreach (var item in sequences.First())
{
string current = (prefix == "") ? item.ToString() : prefix + "_" + item;
var remaining = sequences.Skip(1);
if (!remaining.Any())
{
yield return current;
}
else
{
foreach (var s in Combine(current, remaining))
yield return s;
}
}
}
}
}

C# (String.StartsWith && !String.EndsWith && !String.Contains) using a List

I am a newbie in C#, and I am having problems.
I have 2 List, 2 strings and a getCombinations(string) method that
returns all combinations of a string as List;
How do i validate if a subjectStrings element does not
StartWith && !EndsWith && !Contains (or !StartWith && !EndsWith && Contains, etc.)
for every combinations of startswithString, endswithString and containsString?
Here is my code in StartWith && !EndsWith
(if you want to see it running: http://ideone.com/y8JZkK)
using System;
using System.Collections.Generic;
using System.Linq;
public class Test
{
public static void Main()
{
List<string> validatedStrings = new List<string>();
List<string> subjectStrings = new List<string>()
{
"con", "cot", "eon", "net", "not", "one", "ten", "toe", "ton",
"cent", "cone", "conn", "cote", "neon", "none", "note", "once", "tone",
"cento", "conte", "nonce", "nonet", "oncet", "tenon", "tonne",
"nocent","concent", "connect"
}; //got a more longer wordlist
string startswithString = "co";
string endswithString = "et";
foreach(var z in subjectStrings)
{
bool valid = false;
foreach(var a in getCombinations(startswithString))
{
foreach(var b in getCombinations(endswithString))
{
if(z.StartsWith(a) && !z.EndsWith(b))
{
valid = true;
break;
}
}
if(valid)
{
break;
}
}
if(valid)
{
validatedStrings.Add(z);
}
}
foreach(var a in validatedStrings)
{
Console.WriteLine(a);
}
Console.WriteLine("\nDone");
}
static List<string> getCombinations(string s)
{
//Code that calculates combinations
return Permutations.Permutate(s);
}
}
public class Permutations
{
private static List<List<string>> allCombinations;
private static void CalculateCombinations(string word, List<string> temp)
{
if (temp.Count == word.Length)
{
List<string> clone = temp.ToList();
if (clone.Distinct().Count() == clone.Count)
{
allCombinations.Add(clone);
}
return;
}
for (int i = 0; i < word.Length; i++)
{
temp.Add(word[i].ToString());
CalculateCombinations(word, temp);
temp.RemoveAt(temp.Count - 1);
}
}
public static List<string> Permutate(string str)
{
allCombinations = new List<List<string>>();
CalculateCombinations(str, new List<string>());
List<string> combinations = new List<string>();
foreach(var a in allCombinations)
{
string c = "";
foreach(var b in a)
{
c+=b;
}
combinations.Add(c);
}
return combinations;
}
}
Output:
con
cot
cone
conn
cote <<<
conte <<<
concent
connect
Done
if(z.StartsWith(a) && !z.EndsWith(b))
var b can be "et" and "te", but cote and conte endswith "te",
why it is still added in my validated strings?
Thanks in advance.

z.StartsWith(a) && !z.EndsWith(b)
check below combination
z ="cote"
a ="co"
b ="te"
so z start with "co" and z not end with "te", your condition pass and cote will add to list
i would try as below
var sw =getCombinations(startswithString);
var ew = getCombinations(endswithString);
var result = subjectStrings.Where(z=>
sw.Any(x=>z.StartsWith(x) &&
!ew.Any(y=>z.EndsWith(y))))
.ToList();
DEMO
output :
con
cot
cone
conn
concent
connect

foreach(var b in getCombinations(endswithString))
{
if(z.StartsWith(a) && !z.EndsWith(b))
{
valid = true;
break;
}
}
here you are setting valid to true as soon as there is match for !z.EndsWith(b) and you are not traversing the whole list of permutations available.
since "cote" doesn't end with "et" it is a match and valid is set to true and the code breaks.
So that's why "cote" is added to your list of valid strings. So is the case with "conte".
What you want to do is :
List<string> startsWithCombination = getCombinations("co");
List<string> endsWithCombination = getCombinations("et");
foreach (var z in subjectStrings)
{
bool isStartMatchFound = startsWithCombination.Any(b => z.StartsWith(b));
if (isStartMatchFound)
{
bool isEndMatchFound = endsWithCombination.Any(b => z.EndsWith(b));
if (!isEndMatchFound)
{
validatedStrings.Add(z);
}
}
}