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C# Regex match case - split string and write to file output

Basically I have a text file of records in this format:
(1909, 'Ford', 'Model T'),
(1926, 'Chrysler', 'Imperial'),
(1948, 'Citroën', '2CV'),
That I want to output to a text file in the following format
new Vehicle() { Id = 1, Year = 1909, Make = "Ford", Model = "Model T" },
new Vehicle() { Id = 2, Year = 1926, Make = "Chrysler", Model = "Imperial" },
new Vehicle() { Id = 3, Year = 1948, Make = "Citroën", Model = "2CV" },
I know I need to split each line in to the relevant text sections, e.g. trying to follow something like this SO question. But have hit mental block on how to get the relevant matching string sections for Year, Make and Model.
So far I have found this, that finds everthing between the parentheses:
\(([^()]+)\)
But not sure how to then group the the values and split by the commas:
Any help greatly appreciated.

Regex to get them in groups:
\((\d+),\s+[']([\w\së]+)['],\s+[']([\w\s]+)[']\)[,]*
Make note there is problem about Citroën => You have to enter all the special symbols not within a-z, A-Z (like ë ü ÿ etc..)
To use in code, You will get the groups 1st:
string cars = #"(1909, 'Ford', 'Model T'),"
string pattern = #"\((\d+),\s+[']([\w\së]+)['],\s+[']([\w\s]+)[']\)[,]*";
var lResult = Regex.Match(cars, pattern);
if(lResult.Success)
foreach( var iGroup in lResult.Groups)
Console.WriteLine(iGroup);
In lResult.Groups You got the info about car, You have just output it to the file as You need.
C# 6.0:
Console.WriteLine($"new Vehicle() {{ Id = 1, Year = {lResults.Groups[1]}, Make = \"{lResults.Groups[2]}\", Model = \"{lResults.Groups[3]}\"}},");
Old syntax:
Console.WriteLine(#"new Vehicle() { Id = 1, Year = "+ lMatch.Groups[1]+", Make = "+ lMatch.Groups[2] + ", Model = "+ lMatch.Groups[3] + " },");
Once You get this automatized into for loops, You can add Id easily.
My example have in Groups[0] whole string, so this is why my indexing starting from 1 to 3.
As #Toto said, \w already includes \d, there is no need to write it then.

Why not use string.Split(',')? Would be faster than Regex and suits for you (first delete the last ',' of each line, of course.

if you are willing to use a parser framework (which is maybe a little bit of an overkill), you could use for example sprache. Example without proper error handling:
Parser<string> stringContent =
from open in Parse.Char('\'').Once()
from content in Parse.CharExcept('\'').Many().Text()
from close in Parse.Char('\'').Once()
select content;
Parser<string> numberContent = Parse.Digit.AtLeastOnce().Text();
Parser<string> element = stringContent.XOr(numberContent);
Parser<List<string>> elements =
from e in element.DelimitedBy(Parse.Char(',').Token())
select e.ToList();
Parser<List<string>> parser =
from open in Parse.Char('(').Once()
from content in elements
from close in Parse.Char(')').Once()
select content;
var input = new List<string> { "(1909, 'Ford', 'Model T')", "(1926, 'Chrysler', 'Imperial')", "(1948, 'Citroën', '2CV')" };
foreach (var line in input)
{
var parsed = parser.Parse(line);
var year = Int32.Parse(parsed[0]);
var make = parsed[1];
var model = parsed[2];
Console.WriteLine(">> " + year + " " + make + " " + model);
}

You can use this snippet based on named capture groups:
var cars = new List<string>() {
"(1909, 'Ford', 'Model T')",
"(1926, 'Chrysler', 'Imperial')",
"(1948, 'Citroën', '2CV')",
};
var regex = #"(?<Year>\d+).*?'(?<Brand>.*?)'.*?'(?<Model>.*?)'";
foreach (var car in cars)
{
var match = Regex.Match(car, regex);
if (match.Success)
{
Console.WriteLine($"{match.Groups["Brand"]} make {match.Groups["Model"]} in {match.Groups["Year"]}");
}
}
Which will print:
Ford make Model T in 1909
Chrysler make Imperial in 1926
Citroën make 2CV in 1948

JSON Deserialize Error: The given key was not present in the dictionary

I'm trying to output JSON to a drop down list in a web form. I've managed to get this far:
WebClient client = new WebClient();
string getString = client.DownloadString("http://myfeed.com/app_feed.php");
JavaScriptSerializer serializer = new JavaScriptSerializer();
dynamic item = serializer.Deserialize<object>(getString);
string name = item["title"];
return name;
This brings back the feed ok but it runs into an error on the line:
string name = item["title"];
Bringing back this error:
Additional information: The given key was not present in the dictionary.
This is a sample of my feed:
{"apps":[{"title":"title1","description":"description1"},
{"title":"title2","description":"description2"},
{"title":"title3","description":"description3"}
So I thought that I was referencing the first title and I was planning to loop through them:
string name = item["title"];
But obviously not!
I have looked on Stackoverflow but I can't find an answer that I can apply to my own code.

title is inside another key apps and its an array so you should iterate it, I show you just select first one using index 0
string name = item["apps"][0]["title"];
you can access all by foreach
foreach (var ap in item["apps"])
{
Console.WriteLine(ap["title"]);
}

First, your JSON is invalid. Second: you need to loop over your items, as it is an array. If you want to access the first one, you could do: item["apps"][0]["title"]
Looping through all items:
var str = #"{""apps"":[{""title"":""title1"",""description"":""description1""},
{""title"":""title2"",""description"":""description2""},
{""title"":""title3"",""description"":""description3""}]}";
var serializer = new JavaScriptSerializer();
dynamic obj = serializer.Deserialize<object>(str);
foreach (var item in obj["apps"])
{
Console.WriteLine("item title: " + item["title"]);
}

Json.NET adding backslash while returning json serialized string

I am trying to serialize a list to json string using Json.NET but the return string has backslash within it, which in turn is failing a json parsing.
var x = from d in entities.Books.ToList()
select new
{
ID = d.ID,
BookName = d.BookName
};
return JsonConvert.SerializeObject(x.ToList());
The above code returns
"[{\"ID\":1,\"BookName\":\"MVC Music Store - Tutorial - v3.0\"},{\"ID\":2,\"BookName\":\"Pro.ASP.NET.MVC.3.Framework\"},{\"ID\":3,\"BookName\":\"Application Architecture Guide v2\"},{\"ID\":4,\"BookName\":\"Gang of Four Design Patterns\"},{\"ID\":5,\"BookName\":\"CS4 Pocket Reference\"}]"
which fails all JSON parsing. How can I remove these.

No. it doesn't
class Program
{
class Book
{
public int ID;
public string BookName;
}
static void Main()
{
var books = new List<Book> { new Book { ID = 1, BookName = "A" }, new Book { ID = 2, BookName = "B" } };
var x = from d in books
select new
{
ID = d.ID,
BookName = d.BookName
};
string str = JsonConvert.SerializeObject(x.ToList());
Console.WriteLine(str);
}
}
There could be two problems:
A) You are looking at the result from the debugger. To check for this, Put the JsonConvert in a temporary variable (like I did) and look at it with the debugger. Click on the arrow right of the hourglass and select Text Visualizer.
or
B) The calling method is transforming the object again to Json, so escaping everything.

string str = "Your string with slashes";
str = JToken.Parse({your string here}).ToString();

The JSON object is serialized twice.
I solved by:
Declaring the operation contract of the method response format to return JSON.
I changed the method to return an object instead of a string.
The serializing of Jason will be done automatically behind the scenes.

I was getting the same result, but with doubled escape shashes while I was unit testing some json serialization. Looking at my code I realized I am serializing the "expected" json string instead of the actual .net object. So, passing a json string to JsonConvert.SerializeObject(expectedJsonString) will simply escape it once over. This is how I came here, and this is the answer I wrote, when I realized I just did a coding mistake... Did you just realize yours?

Variable in the dynamic string in C#

I have a module to send message with the SMS. I can put the variable in the string if the message is a static, but the user request the message can be changed whatever their want.
I created this variable
CompanyName
CustomerName
BillNumber
Payment
Example :
From {Company}. Hi Mr/Mrs {CustomerName}, your bill number is
{BillNumber} with a total payment of {Payment}. We want to inform you
the items has been completed and ready for collection.
My current code is work for static message,
string messageSms = "From " +Company+ ". Hi Mr/Mrs "+{CustomerName}+", your bill number is "+{BillNumber}+" with a total payment of "+{Payment}+". We want to inform you the items has been completed and ready for collection.";
But how can be done with dynamic message? How can I detect the variable in the string and set the data on the variable?
I also following with this article but not help so much.

var newString = messageSms.Replace("{Company}", CompanyName)
.Replace("{CustomerName}", CustomerName) // ...etc
Should do it.

Assuming I'm understanding, i think the String.Inject class could be helpful. Picture a named String.Format:
"Hello, {company}!".Inject(new { company = "StackOverflow" });
// "Hello, StackOverflow!"
The other benefit is you can have a hard-coded model and reference direct properties of it. e.g.
class Contact
{
string FirstName;
string LastName;
}
String greeting = "Mr. {FirstName} {LastName}, Welcome to the site ...";
String result = greeting.Inject(new Contact
{
FirstName = "Brad",
LastName = "Christie"
});

You could also use interpolated strings using C# 6.0
var messageSms = $"From {companyName}. Hi {customerName}, your bill number is {billNumber} with a total payment of {payment}.";

I would approach with the following :
string Company;
string CustomerName;
string BillNumber;
string Payment;
string messageSms = $#"
From {Company}. Hi Mr/Mrs {CustomerName}, your bill number is {BillNumber}
with a total payment of {Payment}. We want to inform you the items has been
completed and ready for collection.
";

Try String.Format Method, for example:
string messageSms = String.Format("From {0}. Hi ..{1}, Your..{2} with..{3}. We..",
CompanyName, CustomerName, BillNumber, Payment);

I assume that the easiest way to achieve this (you did not clarify your question) is to use string.Format().
Just use it like this:
string company = ...;
string name= ...;
string billNr= ...;
string payment= ...;
string output = string.Format("From {0}. Hi Mr/Mrs {1}, your bill number is {2} with a total payment of {3}. We want to inform you the items has been completed and ready for collection.", company, name, billNr, payment);

Why not use a StringBuilder instead?
StringBuilder stringBuilder = new StringBuilder("From {Company}.Hi Mr/Mrs {CustomerName}, your bill number is {BillNumber} with a total payment of {Payment}. We want to inform you the items has been completed and ready for collection.");
stringBuilder.Replace("{Company}",CompanyName);
stringBuilder.Replace("{CustomerName}",CustomerName);
stringBuilder.Replace("{BillNumber}",BillNumber);
stringBuilder.Replace("{Payment}",Payment);
string messageSms = stringBuilder.ToString();

To make a reusable solution you could start by declaring an object that contains the replacement values as properties. In this case I simply declare an anonymous object but a normal class would work just as well:
var data = new {
Company = "Stack Overflow",
CustomerName = "Martin Liversage",
BillNumber = 123456,
Payment = 1234.567M.ToString("N2")
};
Notic how I "cheat" and assign a string to Payment. Number and date/time formatting is always a complex issue and I have decided to do the formatting up-front when I declare the data object. You could instead build some more or less elaborate formatting rules into the formatting engine.
Having a data object with properties I can build a dictionary of name/value pairs:
var dictionary = data
.GetType()
.GetProperties()
.ToDictionary(
propertyInfo => propertyInfo.Name,
propertyInfo => propertyInfo.GetValue(data, null)
);
Assuming that format contains the formatting template it is simply a matter of looping over the elements in the dictionary to create the replacement string:
var buffer = new StringBuilder(format);
foreach (var name in dictionary.Keys) {
var value = dictionary[name].ToString();
buffer.Replace("{" + name + "}", value);
}
var message = buffer.ToString();

Deserialize string of name=value format to object

I want to read files, each of which contains a person's details, as below, and convert it to a Person object.
Covert below
id=1
firstName=John
lastName=Smith
To:
public class Person
{
public int Id {get;set;}
public string FirstName{get;set;}
public string LastName{get;set;}
}
Are there .NET built-in methods to do that, or third party library. I cannot find it via google.
Update:
The file format CANNOT be changed.

.NET is really into XML, so you won't find build-in functionality for INI-like formats. But there are a bunch of libs that make it easy to read and write such files, e.g. ini-parser or nini, but you still have to do the mapping to and from objects manually.

You could parse the text with String.Split and LINQ:
Dictionary<string, string> dict = text
.Split(new[] { Environment.NewLine }, StringSplitOptions.None)
.Select(e => e.Split('='))
.ToDictionary(strings => strings[0], strings => strings[1]);
Then use something like Dictionary Adapter.

For example using File.ReadAllLines, a little bit of Linq and String.Substring?
var lines = File.ReadAllLines(path).Select(l => l.Trim());
var idLine = lines.FirstOrDefault(l => l.StartsWith("id=", StringComparison.OrdinalIgnoreCase));
var lNameLine = lines.FirstOrDefault(l => l.StartsWith("lastname=", StringComparison.OrdinalIgnoreCase));
var fNameLine = lines.FirstOrDefault(l => l.StartsWith("firstname=", StringComparison.OrdinalIgnoreCase));
if (idLine != null && lNameLine != null && fNameLine != null)
{
Person person = new Person()
{
Id = int.Parse(idLine.Substring(idLine.IndexOf("=") + 1)),
FirstName = fNameLine.Substring(fNameLine.IndexOf("=") + 1),
LastName = lNameLine.Substring(lNameLine.IndexOf("=") + 1)
};
}
(assuming that there's just one person per file)
But i would use a different format like XML (or a database of course).

I really think you should consider changing your input data format into something more standard (like XML or JSON).
But that does not mean you can't read your file at all. You should just read your text file by your own:
var people = new List<Person>();
using (var stream = File.OpenRead("Input.txt"))
{
using (var reader = new StreamReader(stream))
{
while (!reader.EndOfStream)
{
int id = int.Parse(reader.ReadLine().Substring(3));
string firstName = reader.ReadLine().Substring(10);
string lastName = reader.ReadLine().Substring(9);
var newPerson = new Person()
{
Id = id,
FirstName = firstName,
LastName = lastName
};
people.Add(newPerson);
}
}
}

If you have the data in a format like this:
<Person>
<Id>1</Id>
<FirstName>John</FirstName>
<LastName>Smith</LastName>
</Person>
Then this C# code will desrialise into an instance of Person
//assuming you have a string called "data" that contains the above XML.
XDocument xd=XDocument.Parse(data); //needs System.Xml.Linq for XDocument type.
using(var reader = xd.CreateReader())
{
using(XmlSerializer ser = new XmlSerializer(typeof(Person))
{
Person p = ser.Deserialize(reader) as Person;
//p will be null if it didn't work, so make sure to check it!
}
}
Note that the deserializer is case sensitive so you need to make sure the element cases match the casing of the properties in your class (You can get arond this by decorating your properties with Serializer attributes that tell the serialzer how to map them here)
The plain native serialzer is great for simple objects like this but can trip you up on some data types like char, bool, etc, so do checkout that link on the attributes.
If you wanted to do it from the format you gave in the question, you'd need to write a custom serialiser, in your case my advice would be to read from your file and generate XML from the data using XDocument Hope that helps.