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String interpolation: How do I make this function work with any type

This is a function to work with lists in string interpolation. It takes a List and an inner Func, and it appends the string result of the inner Func called for each member of the list, with a separator.
So the following builds a valid start of an Insert statement...
static void Main(string[] args)
{
var tableName = "customers";
var cols = new List<dynamic>
{
new { Name = "surname"},
new { Name = "firstname"},
new { Name = "dateOfBirth"}
};
Func<List<dynamic>, Func<dynamic, string>, string, string> ForEach = (list, func, separator) =>
{
var bldr = new StringBuilder();
var first = true;
foreach (var obj in list)
{
if (!first)
bldr.Append(separator);
first = false;
bldr.Append(func(obj));
}
return bldr.ToString();
};
var InsertStatement = $"Insert into { tableName } ( {ForEach(cols, col => col.Name, ", ")} )";
Console.WriteLine(InsertStatement);
Console.ReadLine();
}
Outputs...
Insert into customers ( surname, firstname, dateOfBirth )
It works for dynamic. How do I make it work for any type? The outer Func shouldn't care about the Type in the list, it just passes it through to the inner Func.

The .NET framework already gives you a generic function to achieve what you are trying to do String.Join and you can combine it with a LINQ Select statement, which will allow you to use a lambda on a generic type to select the property that you want to print. You can view the source code of these methods if you are interested as they are open source.
using System;
using System.Collections.Generic;
using System.Linq;
public class MyType
{
public string Name { get; set; }
}
public class Program
{
public static void Main()
{
var tableName = "customers";
var cols = new List<MyType>
{
new MyType { Name = "surname"},
new MyType { Name = "firstname"},
new MyType { Name = "dateOfBirth"}
};
var InsertStatement = $"Insert into { tableName } ( {String.Join(", ", cols.Select(col => col.Name))} )";
Console.WriteLine(InsertStatement);
}
}

Replace dynamic with object, or TValue with a type constraint stipulating it must be a class (where TValue : class), and call obj.ToString() instead of just obj
However, this doesn't guarantee it would "work with any type" - for that you need to know that those types all follow a contract to output the desired column name as their string representation. To get more specificity, require that your accepted types must implement some interface eg IColumnName and put that interface into the type constraint instead

You can create the text easily like this:
var query = $"INSERT INTO {tableName}({string.Join(",", cols.Select(x=>x.Name))})";
However, if for learning purpose you are going to handle the case using a generic method, you can create a generic function like the following and then easily use a for loop and strip additional separator using TrimEnd, or as a better option, like String.Join implementation of .NET Framework get enumerator like this:
string Join<TItem>(
IEnumerable<TItem> items, Func<TItem, string> itemTextSelecor, string separator)
{
var en = items.GetEnumerator();
if (!en.MoveNext())
return String.Empty;
var builder = new StringBuilder();
if (en.Current != null)
builder.Append(itemTextSelecor(en.Current));
while (en.MoveNext())
{
builder.Append(separator);
if (en.Current != null)
builder.Append(itemTextSelecor(en.Current));
}
return builder.ToString();
}
And use it this way:
var tableName = "customers";
var cols = new[]
{
new { Name = "surname"},
new { Name = "firstname"},
new { Name = "dateOfBirth"}
};
var InsertStatement = $"INSERT INTO {tableName} ({Join(cols, col => col.Name, ", ")})"
+ $"VALUES({Join(cols, col => $"#{col.Name}", ", ")})";

CSV Delimited to XML - Folder Hierarchy

This is my first time posting so I apologize for any ignorance or failed use of examples.
I have a console app project to create where I have been given a fair few CSV files and I need to create some kind of Parent/Child/Grandchild relationship out of them (XML? maybe? - then I can use that to do the uploads and writes to the DMS with minimal calls - I don't want to be querying if a folder exists over and over)
I am a little out of my depth on this one
I need to know the best way to do this without 3rd party library dependencies, pure C#, using the OLEDB JET provider is most likely required as it will handle the parsing required, there is no order to the CSV files in regards to date, previous years could appear down the list and vice versa.
Here's an example of the CSV output
"DESCRIPTION1","8, 5/8\" X 6.4MM","STRING","filename001.pdf","2016-09-19","1"
"DESCRIPTION2","12, 3/4\" X 6.4MM","STRING","filename001.pdf","2016-09-19","1"
"DESCRIPTION3","12, 3/4\" X 6.4MM","STRING","filename001.pdf","2016-09-19","1"
"another description 20# gw","1","388015","Scan123.pdf","2015-10-24","1"
"another description 20# gw","3","385902","Scan456.pdf","2015-04-14","1"
"STRINGVAL1","273.10 X 9.27 X 6000","45032-01","KHJDWNEJWKFD9101529.pdf","2012-02-03","1"
"STRINGVAL2","273.10 X 21.44 X 6000","7-09372","DJSWH68767681540.pdf","2017-02-03","1"
The end output will be (YEAR/MONTH/FILENAME + (Attributes for each file - these are for eventually updating columns inside a DMS))
Year and Month retrieved from the column with the date
If the YEAR alread exists then it will not be created again
If the month under that year exists it will not be created again
If the filename already exists under that YEAR/MONTH it will not be created again BUT the additional ATTRIBUTES for that FileName will be added to the attributes - "line seperated?"
Required Output:
I have attempted a Linq query to begin to output the possible required XML for me to progress but it outputs every row and does no grouping, I am not familiar with Linq at the moment.
I also ran into issues with the basic escaping on the .Split(',') doing it this way (see original CSV examples above compared to me using TAB separation in my test file and example below) which is why I want the Oledb provider to handle it.
string[] source = File.ReadAllLines(#"C:\Processing\In\mockCsv.csv");
XElement item = new XElement("Root",
from str in source
let fields = str.Split('\t')
select new XElement("Year", fields[4].Substring(0, 4),
new XElement("Month", fields[4].Substring(5, 2),
new XElement("FileName", fields[3]),
new XElement("Description",fields[0]),
new XElement("Length", fields[1]),
new XElement("Type", fields[2]),
new XElement("FileName", fields[3]),
new XElement("Date", fields[4]),
new XElement("Authorised", fields[5]))
)
);
I also need to log every step of the process so I have setup a Logger class
private class Logger
{
private static string LogFile = null;
internal enum MsgType
{
Info,
Debug,
Error
}
static Logger()
{
var processingDetails = ConfigurationManager.GetSection(SECTION_PROCESSINGDETAILS) as NameValueCollection;
LogFile = Path.Combine(processingDetails[KEY_WORKINGFOLDER],
String.Format("Log_{0}.txt", StartTime.ToString("MMMyyyy")));
if (File.Exists(LogFile))
File.Delete(LogFile);
}
internal static void Write(string msg, MsgType msgType, bool isNewLine, bool closeLine)
{
if (isNewLine)
msg = String.Format("{0} - {1} : {2}", DateTime.Now.ToString("dd/MM/yyyy HH:mm:ss"), msgType, msg);
if (closeLine)
Console.WriteLine(msg);
else
Console.Write(msg);
if (String.IsNullOrEmpty(LogFile))
return;
try
{
using (StreamWriter sw = new StreamWriter(LogFile, true))
{
if (closeLine)
sw.WriteLine(msg);
else
sw.Write(msg);
}
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
}
}
Used as such
Logger.Write(String.Format("Reading records from csv file ({0})... ",
csvFile), Logger.MsgType.Info, true, false);

Try following. If you are reading from a file use StreamReader instead of StringReader :
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;
using System.Xml.Linq;
using System.IO;
using System.Text.RegularExpressions;
namespace ConsoleApplication74
{
class Program
{
static void Main(string[] args)
{
string input =
"\"DESCRIPTION1\",\"8, 5/8 X 6.4MM\",\"STRING\",\"filename001.pdf\",\"2016-09-19\",\"1\"\n" +
"\"DESCRIPTION2\",\"12, 3/4 X 6.4MM\",\"STRING\",\"filename001.pdf\",\"2016-09-19\",\"1\"\n" +
"\"DESCRIPTION3\",\"12, 3/4 X 6.4MM\",\"STRING\",\"filename001.pdf\",\"2016-09-19\",\"1\"\n" +
"\"another description 20# gw\",\"1\",\"388015\",\"Scan123.pdf\",\"2015-10-24\",\"1\"\n" +
"\"another description 20# gw\",\"3\",\"385902\",\"Scan456.pdf\",\"2015-04-14\",\"1\"\n" +
"\"STRINGVAL1\",\"273.10 X 9.27 X 6000\",\"45032-01\",\"KHJDWNEJWKFD9101529.pdf\",\"2012-02-03\",\"1\"\n" +
"\"STRINGVAL2\",\"273.10 X 21.44 X 6000\",\"7-09372\",\"DJSWH68767681540.pdf\",\"2017-02-03\",\"1\"\n";
string pattern = "\\\"\\s*,\\s*\\\"";
string inputline = "";
StringReader reader = new StringReader(input);
XElement root = new XElement("Root");
while ((inputline = reader.ReadLine()) != null)
{
string[] splitLine = Regex.Split(inputline,pattern);
Item newItem = new Item() {
description = splitLine[0].Replace("\"",""),
length = splitLine[1],
type = splitLine[2],
filename = splitLine[3],
date = DateTime.Parse(splitLine[4]),
authorized = splitLine[5].Replace("\"", "") == "1" ? true : false
};
Item.items.Add(newItem);
}
foreach(var year in Item.items.GroupBy(x => x.date.Year).OrderBy(x => x.Key))
{
XElement newYear = new XElement("_" + year.Key.ToString());
root.Add(newYear);
foreach(var month in year.GroupBy(x => x.date.Month).OrderBy(x => x.Key))
{
XElement newMonth = new XElement("_" + month.Key.ToString());
newYear.Add(newMonth);
newMonth.Add(
month.OrderBy(x => x.date).Select(x => new XElement(
x.filename,
string.Join("\r\n", new object[] {
x.description,
x.length,
x.type,
x.date.ToString(),
x.authorized.ToString()
}).ToList()
)));
}
}
}
}
public class Item
{
public static List<Item> items = new List<Item>();
public string description { get; set; }
public string length { get; set; }
public string type { get; set; }
public string filename { get; set; }
public DateTime date { get; set; }
public Boolean authorized { get; set; }
}
}

Manage complex string array in C#

I want to use a string array stored in the web.config to easily change its values, this is in the format: full_w=670|small_w=100,q=low|tiny_h=30,c=true. Each template is split by the | (pipe) and then each of those sets comprises of a name (left of _) and its corresponding values (right of _), the values can be several and each separated by the , (comma). I think this possibly qualifies for a 3D array, I just can't seem to get an easy way to read this in a sensible manner. Any ideas or solutions as to the best way to read/manage the data from this string?
Basically, in the end I want to be able to call the template small and read its values which in this case are width=100 and quality=low.

Here's the function I wrote to parse one of these settings strings:
public static Dictionary<string, Dictionary<string, string>> getSettings(string settingsStr)
{
return settingsStr.Split('|').ToDictionary(
template => template.Split('_')[0],
template => template.Split('_')[1].Split(',').ToDictionary(
setting => setting.Split('=')[0],
setting => setting.Split('=')[1]));
}
It just uses a lot of string .Splitting and .ToDictionarying.
Here's the test, showing that it works:
var result = getSettings("full_w=670|small_w=100,q=low|tiny_h=30,c=true");
/*
result = {
[ "full" => [ "w" => "670" ] ]
[ "small" => [ "w" => "100", "q" => "low" ] ]
[ "tiny" => [ "h" => "30", "c" => "true" ] ]
}
*/
To read the values w and q from template small, you can do this:
int width = int.Parse(result["small"]["w"]);
string quality = result["small"]["q"];
Edit: As an added bonus, if you want to convert the Dictionary<string, Dictionary<string, string>> back into a single settings sting, you can use this method:
public static string getSettingsStr(Dictionary<string, Dictionary<string, string>> settings)
{
return string.Join("|",
settings.Select(kvp =>
kvp.Key + "_" + string.Join(",",
kvp.Value.Select(setting =>
setting.Key + "=" + setting.Value))));
}
Use:
string settingsStr = getSettingsStr(result);
// settingsStr = "full_w=670|small_w=100,q=low|tiny_h=30,c=true"
If you want to check that a specific template or setting exists, then use the .ContainsKey() method:
// If I have "Dictionary<string, Dictionary<string, string>> settings;"
int width = -1;
string quality = null;
if (settings.ContainsKey("small"))
{
if (settings["small"].ContainsKey("w"))
width = int.Parse(settings["small"]["w"]);
if (settings["small"].ContainsKey("q"))
quality = settings["small"]["q"];
}

Have you considered using plain old XML Serialization with your own plain old C# objects. Here is an example:
public class Program
{
static void Main(string[] args)
{
var data = new MyConfig[2];
for (int i = 0; i < 2; i++)
{
data[i] = new MyConfig { Name = "Name" + i };
data[i].Properties = new MyConfigAttribute[]
{
new MyConfigAttribute { Name = "Property Name " + i, Value = "Property Value " + i },
new MyConfigAttribute { Name = "2nd Property Name " + i, Value = "2nd Property Value " + i },
};
}
var serializer = new XmlSerializer(typeof(MyConfig[]));
using (StreamWriter tw = File.CreateText(#"c:\temp\myconfig.xml"))
{
serializer.Serialize(tw, data);
}
using (StreamReader tw = File.OpenText(#"c:\temp\myconfig.xml"))
{
var readBack = serializer.Deserialize(tw);
}
Console.ReadLine();
}
[XmlRoot("MY_CONFIG")]
public class MyConfig
{
[XmlElement("NAME")]
public string Name { get; set; }
[XmlArray]
[XmlArrayItem(typeof(MyConfigAttribute))]
public MyConfigAttribute[] Properties { get; set; }
}
[XmlRoot("MY_CONFIG_ATTRIBUTE")]
public class MyConfigAttribute
{
[XmlElement("ATTRIBUTE_NAME")]
public string Name { get; set; }
[XmlElement("ATTRIBUTE_VALUE")]
public string Value { get; set; }
}
}
Basically, you create a class to store your individual attributes (MyConfigAttribute in this case), wrap it in another class to provide your name for a group of related attributes (MyConfig in this case), then use normal XML Serialization to write the settings out to an individual XML file, like this section of the code
var serializer = new XmlSerializer(typeof(MyConfig[]));
using (StreamWriter tw = File.CreateText(#"c:\temp\myconfig.xml"))
{
serializer.Serialize(tw, data);
}
You can read it back to objects again using this section of the code:
using (StreamReader tw = File.OpenText(#"c:\temp\myconfig.xml"))
{
var readBack = serializer.Deserialize(tw);
}
The advantage of this is:
It is simple to understand and use
You can add features to your custom class, e.g. to add values to the array of properties, thereby lending itself to wrapping a custom screen around it.
Look up C# XML Serialization on Google!

How to convert List to a string and back

I retrieved a list of users from database, something like
List<User> users = <..list of users from db...>
Name, LastName, DateOfBirth //multidimensional array??
Now I want to store this list as a string and I want be able to reuse it i.e.
string strUsers = users.ToArray().ToString();
How to recreate a list of users from strUsers?
Is it possible?

Use the string.Join method, e.g.
var joined = string.Join(",", users.Select(u => u.Name));
This would give you a single string of user's names separated by ','.
Or for multiple columns:
var joined = string.Join(",",
users.Select(u => u.FirstName + " " + u.LastName ));
You can reverse the process using string.Split, e.g.
var split = joined.Split( new [] {','} );

If you have a lot of users and a lot of columns, it would be better to write your own custom converter class.
public static class UsersConverter
{
// Separates user properties.
private const char UserDataSeparator = ',';
// Separates users in the list.
private const char UsersSeparator = ';';
public static string ConvertListToString(IEnumerable<User> usersList)
{
var stringBuilder = new StringBuilder();
// Build the users string.
foreach (User user in usersList)
{
stringBuilder.Append(user.Name);
stringBuilder.Append(UserDataSeparator);
stringBuilder.Append(user.Age);
stringBuilder.Append(UsersSeparator);
}
// Remove trailing separator.
stringBuilder.Remove(stringBuilder.Length - 1, 1);
return stringBuilder.ToString();
}
public static List<User> ParseStringToList(string usersString)
{
// Check that passed argument is not null.
if (usersString == null) throw new ArgumentNullException("usersString");
var result = new List<User>();
string[] userDatas = usersString.Split(UsersSeparator);
foreach (string[] userData in userDatas.Select(x => x.Split(UserDataSeparator)))
{
// Check that user data contains enough arguments.
if (userData.Length < 2) throw new ArgumentException("Users string contains invalid data.");
string name = userData[0];
int age;
// Try parsing age.
if (!int.TryParse(userData[1], out age))
{
throw new ArgumentException("Users string contains invalid data.");
}
// Add to result list.
result.Add(new User { Name = name, Age = age });
}
return result;
}
}
You will win performance wise using the StringBuilder to build up your users string. You could also easily expand the converter to take account different separators/additional logic etc.
If you need a more generic solution (to be able to use for any class), you could create a converter which uses reflection to iterate over all the public fields, get/set properties to see what can be extracted as string and later reverse the process to convert your string back to the list.

I think what you're looking for is something that lets you dump all users to a string and get the users back from the string, correct?
I suggest something like this:
Add a method that returns an XElement to the Users type:
public XElement GetXElement()
{
return new XElement("User", new XElement("Name", this.FirstName)) //and so on...
}
and then one that decodes the string into a user:
static User GetUserFromXElement(string xml)
{
XElement temp = XElement.Parse(xml);
User temp = new User();
foreach (XElement inner in temp.Elements())
{
switch inner.Name
{
case "Name":
temp.Name = inner.Value
break;
//whatever
}
}
}
And then do this:
public string UsersToElements (List<Users> toWrite)
{
Stringbuilder sb = new StringBuilder();
StringWriter sw = new StringWriter(sb);
XElement root = new XElement("root");
XDocument temp = new XDocument(root);
foreach (User user in toWrite)
{
root.Append(user.GetXElement());
}
temp.Save(sw);
return sw.ToString();
}
and this:
public List<Users> ElementsToUsers (string xml)
{
List<Users> usrsList = new List<Users>();
XDocument temp = XDocument.Load(xml);
foreach (XElement e in XDocument.Root.Elements())
{
usrsList.Append(Users.GetUserFromXElement(e));
}
return usrsList;
}
JSON solution (using JSON.NET)
public JObject GetJObject()
{
return new JObject("user", new JProperty("name", this.FirstName)); //so on
}
static User GetUserFromJObject(string json)
{
JObject obj = JObject.Parse(json);
return new User() { FirstName = (string)obj["user"]["name"] }; //so on
}
public string UsersToElements (List<Users> users)
{
JObject root = new JObject(from usr in users select new JAttribute("user", usr.GetJObject());
return root.ToString();
}
public List<users> ElementsToUsers(string json)
{
List<Users> users = new List<Users>();
JObject temp = JObject.Parse(json);
foreach (JObject o in (JEnumerable<JObject>)temp.Children())
{
users.Add(Users.GetUserFromJObject(o.ToString());
}
return users;
}
I have no idea if ths works :/ (well the XML I know it does, not so sure about the JSON)

Use this code
string combindedString = string.Join( ",", myList );
var Array = combindedString.Split( new [] {','} );

How to use a dynamic CSV delimiter with FileHelpers?

Question:
I need to read a CSV file.
I use the FileHelpers library to achieve this.
The problem is I need a dynamic delimiter (user defined), meaning anything can be delimiter (Comma, semicolon, tab, newline, but also anything else).
The problem is, FileHelpers defines the delimiter in an attribute, which means at compile-time. This makes it impossible to do it dynamically.
What I can do is declare a new class, which inherits from one base class, and set the delimiter on this new class.
[FileHelpers.DelimitedRecord(",")]
public class CommaCustomer : BaseCustomer
{
}
That way I only have to make changes in the base class for every new delimiter.
The problem is, this is I can't (and don't want to) create a child class for every possible delimiter.
This is the code I have so far:
using System;
using System.Data;
using System.IO;
//using FileHelpers;
//using FileHelpers.RunTime;
namespace Examples
{
class MainClass
{
[STAThread]
static void Main()
{
FileHelpers.FileHelperEngine engine = new FileHelpers.FileHelperEngine(typeof(SemicolonCustomer));
// To read use:
string str = #"D:\Username\Desktop\FileHelpers_Examples_CSharp_VbNet\Data\SemicolonCustomers.txt";
//str = #"D:\Username\Desktop\FileHelpers_Examples_CSharp_VbNet\Data\CustomersDelimited.txt";
SemicolonCustomer[] custs = (SemicolonCustomer[])engine.ReadFile(str);
//Customer[] custs = (Customer[]) engine.ReadFile("yourfile.txt");
foreach (SemicolonCustomer cli in custs)
{
Console.WriteLine();
Console.WriteLine("Customer: " + cli.CustId.ToString() + " - " + cli.Name);
Console.WriteLine("Added Date: " + cli.AddedDate.ToString("d-M-yyyy"));
Console.WriteLine("Balance: " + cli.Balance.ToString());
Console.WriteLine();
Console.WriteLine("-----------------------------");
} // Next cli
Console.ReadKey();
Console.WriteLine("Writing data to a delimited file...");
Console.WriteLine();
// To write use:
//engine.WriteFile("myyourfile.txt", custs);
//If you are using .NET 2.0 or greater is
//better if you use the Generics version:
// FileHelperEngine engine = new FileHelperEngine<Customer>();
// To read use (no casts =)
// Customer[] custs = engine.ReadFile("yourfile.txt");
// To write use:
// engine.WriteFile("yourfile.txt", custs);
} // End Sub Main
} // End Class MainClass
//------------------------
// RECORD CLASS (Example, change at your will)
// TIP: Remember to use the wizard to generate this class
public class BaseCustomer
{
public int CustId;
public string Name;
public decimal Balance;
[FileHelpers.FieldConverter(FileHelpers.ConverterKind.Date, "ddMMyyyy")]
public DateTime AddedDate;
}
[FileHelpers.DelimitedRecord(";")]
public class SemicolonCustomer : BaseCustomer
{
}
[FileHelpers.DelimitedRecord(",")]
public class CommaCustomer : BaseCustomer
{
}
}
Is it somehow possible at runtime to compile a child class
[FileHelpers.DelimitedRecord(\"" + delimiter + "\")]
public class AnyDelimiterCustomer : BaseCustomer
{
}
And then reference this runtime compiled class in code ?

I just realized there is a DelimitedFileEngine which solves your problem another way.
You can just go
var engine = new DelimitedFileEngine(typeof(BaseCustomer));
engine.Options.Delimiter = ",";
It seems that BaseCustomer needs to be decorated with a [DelimitedRecord] attribute, otherwise an exception is raised but the delimiter is overridden by whatever is supplied to engine.Options.Delimiter.
The following example imports a comma delimited record using a format which is marked as bar delimited.
[DelimitedRecord("|")]
public class Format1
{
public string Field1;
public string Field2;
public string Field3;
public string Field4;
}
static void Main(string[] args)
{
var engine = new DelimitedFileEngine(typeof(Format1));
// change the delimiter
engine.Options.Delimiter = ",";
// import a comma separated record
object[] importedObjects = engine.ReadString(#"a,b,c,d");
foreach (object importedObject in importedObjects)
{
if (importedObject is Format1)
{
Format1 format1 = (Format1)importedObject;
// process it (for example, check the values)
Assert.AreEqual("a", format1.Field1);
Assert.AreEqual("b", format1.Field2);
Assert.AreEqual("c", format1.Field3);
Assert.AreEqual("d", format1.Field4);
}
}
}

No thats not possible.
But you can use the FileHelper DelimitedClassBuilder to build a dynamic file parser where you can set the delimiter at runtime:
DelimitedClassBuilder dcb = new DelimitedClassBuilder("Name",
"Here goes your col separator");
// You have to build your field definitions by hand now
dcb.AddField("FieldName", typeof(decimal));
...
// build the engine
DelimitedFileEngine fileEngine = new DelimitedFileEngine(dcb.CreateRecordClass());
// read the file
dynamic[] data = fileEngine.ReadFile(filePath);

You can use runtime classes. You have two choices. Either compile your class from a string
For instance
// The class definition
public string mClass =
#"
[DelimitedRecord(""" + delimiter + #""")]
public class BaseCustomer
{
public int CustId;
public string Name;
public decimal Balance;
[FileHelpers.FieldConverter(FileHelpers.ConverterKind.Date, ""ddMMyyyy"")]
public DateTime AddedDate;
}
";
Type t = ClassBuilder.ClassFromString(mClass);
FileHelperEngine engine = new FileHelperEngine(t);
DataTable = engine.ReadFileAsDT("test.txt");
Or alternatively, you can use the DelimitedClassBuilder class.
DelimitedClassBuilder cb = new DelimitedClassBuilder("BaseCustomer", delimiter);
cb.AddField("CustId", typeof(int));
cb.LastField.TrimMode = TrimMode.Both;
cb.LastField.FieldNullValue = 0;
cb.AddField("Balance", typeof(Decimal));
cb.AddField("AddedDate", typeof(DateTime));
engine = new FileHelperEngine(cb.CreateRecordClass());
DataTable dt = engine.ReadFileAsDT("test.txt");

It is possible.
But only by moving the serialization type into a separate assembly.
Like this:
using System;
using System.Collections.Generic;
using System.Windows.Forms;
namespace FlaechenupdateScript
{
static class Program
{
// http://www.codeproject.com/KB/cs/runtimecompiling.aspx
private static System.Reflection.Assembly BuildAssembly(string code)
{
Microsoft.CSharp.CSharpCodeProvider provider =
new Microsoft.CSharp.CSharpCodeProvider();
System.CodeDom.Compiler.ICodeCompiler compiler = provider.CreateCompiler();
System.CodeDom.Compiler.CompilerParameters compilerparams = new System.CodeDom.Compiler.CompilerParameters();
string strLocation = System.Reflection.Assembly.GetExecutingAssembly().Location;
string strBasePath = System.IO.Path.GetDirectoryName(strLocation);
string strSerializationTypes = System.IO.Path.Combine(strBasePath, "SerializationTypes.dll");
string strFileHelpersLocation = System.IO.Path.Combine(strBasePath, "FileHelpers.dll");
compilerparams.ReferencedAssemblies.Add(strSerializationTypes);
compilerparams.ReferencedAssemblies.Add(strFileHelpersLocation);
compilerparams.GenerateExecutable = false;
compilerparams.GenerateInMemory = true;
System.CodeDom.Compiler.CompilerResults results =
compiler.CompileAssemblyFromSource(compilerparams, code);
if (results.Errors.HasErrors)
{
System.Text.StringBuilder errors = new System.Text.StringBuilder("Compiler Errors :\r\n");
foreach (System.CodeDom.Compiler.CompilerError error in results.Errors)
{
errors.AppendFormat("Line {0},{1}\t: {2}\n",
error.Line, error.Column, error.ErrorText);
}
throw new Exception(errors.ToString());
}
else
{
return results.CompiledAssembly;
}
} // End Function BuildAssembly
public static Type GetClassType(Type tt, string strDelimiter)
{
string strFullTypeName = tt.FullName;
string strTypeUniqueName = System.Guid.NewGuid().ToString() + System.Guid.NewGuid().ToString() + System.Guid.NewGuid().ToString() + System.Guid.NewGuid().ToString();
strTypeUniqueName = "_" + strTypeUniqueName.Replace("-", "_");
string xx = #"
namespace CrapLord
{
[FileHelpers.IgnoreFirst]
[FileHelpers.IgnoreEmptyLines]
[FileHelpers.DelimitedRecord(""" + strDelimiter + #""")]
public class " + strTypeUniqueName + #" : " + strFullTypeName + #"
{
}
}
";
System.Reflection.Assembly a = BuildAssembly(xx);
var o = a.CreateInstance("CrapLord." + strTypeUniqueName);
Type t = o.GetType();
//System.Reflection.MethodInfo mi = t.GetMethod("EvalCode");
//var s = mi.Invoke(o, null);
return t;
}
/// <summary>
/// Der Haupteinstiegspunkt für die Anwendung.
/// </summary>
[STAThread]
static void Main()
{
//Application.EnableVisualStyles();
//Application.SetCompatibleTextRenderingDefault(false);
//Application.Run(new Form1());
Type t = GetClassType(typeof(Tools.Serialization.CSV.Customer), ",");
//FileHelpers.FileHelperEngine engine = new FileHelpers.FileHelperEngine(typeof(SemicolonCustomer));
FileHelpers.FileHelperEngine engine = new FileHelpers.FileHelperEngine(t);
string str = "path/to/datafile";
Tools.Serialization.CSV.Customer[] custs = (Tools.Serialization.CSV.Customer[])engine.ReadFile(str);
//Customer[] custs = (Customer[]) engine.ReadFile("yourfile.txt");
foreach (Tools.Serialization.CSV.Customer cli in custs)
{
Console.WriteLine();
Console.WriteLine("Customer: " + cli.CustId.ToString() + " - " + cli.Name);
Console.WriteLine("Added Date: " + cli.AddedDate.ToString("d-M-yyyy"));
Console.WriteLine("Balance: " + cli.Balance.ToString());
Console.WriteLine();
Console.WriteLine("-----------------------------");
} // Next cli
Console.WriteLine(Environment.NewLine);
Console.WriteLine(" --- Press any key to continue --- ");
Console.ReadKey();
}
}
}
SerializationTypes Assembly:
using System;
using System.Collections.Generic;
using System.Text;
namespace Tools.Serialization.CSV
{
//------------------------
// RECORD CLASS (Example, change at your will)
// TIP: Remember to use the wizard to generate this class
public class Customer
{
public int CustId;
public string Name;
public decimal Balance;
[FileHelpers.FieldConverter(FileHelpers.ConverterKind.Date, "ddMMyyyy")]
public DateTime AddedDate;
}
}

Maybe you want to use the TextFieldParser from Microsoft.VisualBasic.FileIO Namespace:
string[] fields;
string[] delimiter = new string[] { "|" };
using (Microsoft.VisualBasic.FileIO.TextFieldParser parser =
new Microsoft.VisualBasic.FileIO.TextFieldParser(filename))
{
parser.Delimiters = delimiter;
parser.HasFieldsEnclosedInQuotes = false;
while (!parser.EndOfData)
{
fields = parser.ReadFields();
//Do what you need
}
}

adding a cast solves the problem for me (FileHelpers V3.5.1)
var engine = new DelimitedFileEngine(typeof(BaseCustomer));
((FileHelpers.Options.DelimitedRecordOptions)engine.Options).Delimiter=",";