i am trying to write two different Objects in one row with the C# library CSVHelper.
It should look something like this:
obj1 obj2
-----------|------------
record1 record1
record2 record2
When register the class maps for these two objects and then call WriteRecords(List) and WriteRecords(List) these objects are written but they are not in the same row. Instead the records of obj2 are written in the rows following the records of obj1.
It looks like this:
obj1
----------
record1
record2
obj2
----------
record1
record2
Program.cs:
string fileReadDirectory =
Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory), "Stuecklisten");
string fileWriteDirectory =
Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory), "Stueckliste.csv");
List<string> files = Directory.GetFiles(fileReadDirectory).ToList();
List<Part> parts = new List<Part>();
List<PartsPerList> partsPerLists = new List<PartsPerList>();
foreach (string file in files)
{
//Reads records from Excel File
CsvReader reader = new CsvReader(new ExcelParser(file));
reader.Context.RegisterClassMap<ExcelSheetMap>();
IEnumerable<Part>? excelRecords = reader.GetRecords<Part>();
foreach (var record in excelRecords)
{
PartsPerList partsPerList = new PartsPerList();
partsPerList.Listname = file;
if (parts.Any(p => p.ManufacturerNr == record.ManufacturerNr))
{
Part part = parts.SingleOrDefault(p => p.ManufacturerNr == record.ManufacturerNr) ?? new Part();
part.TotalQuantity += record.TotalQuantity;
}
else
{
parts.Add(record);
}
partsPerLists.Add(partsPerList);
}
}
using (var stream = File.Open(fileWriteDirectory, FileMode.Create))
using (var streamWriter = new StreamWriter(stream))
using (var writer = new CsvWriter(streamWriter,CultureInfo.InvariantCulture))
{
writer.Context.RegisterClassMap<ExcelSheetMap>();
writer.Context.RegisterClassMap<ManufacturerPartsMap>();
writer.WriteHeader(typeof(Part));
writer.WriteRecords(parts);
writer.WriteHeader(typeof(PartsPerList));
writer.WriteRecords(partsPerLists);
}
Part.cs:
public class Part
{
// public int Quantity { get; set; }
public int TotalQuantity { get; set; }
public string Description { get; set; } = string.Empty;
public string Designator { get; set; } = string.Empty;
public string Case { get; set; } = string.Empty;
public string Value { get; set; } = string.Empty;
public string Tolerance { get; set; } = string.Empty;
public string Remark { get; set; } = string.Empty;
public string PartNumber { get; set; } = string.Empty;
public string Manufacturer { get; set; } = string.Empty;
public string ManufacturerNr { get; set; } = string.Empty;
public string RoHS { get; set; } = string.Empty;
public string Nachweis { get; set; } = string.Empty;
}
Part Classmap:
public sealed class ExcelSheetMap : ClassMap<Part>
{
public ExcelSheetMap()
{
// Map(m => m.Quantity).Name("Qty per pcs");
Map(m => m.TotalQuantity).Index(0);
Map(m => m.Description).Name("description");
Map(m => m.Designator).Name("designator");
Map(m => m.Case).Name("case");
Map(m => m.Value).Name("value");
Map(m => m.Tolerance).Name("tolerance");
Map(m => m.Remark).Name("remark");
Map(m => m.PartNumber).Name("partnumber");
Map(m => m.Manufacturer).Name("manufacturer");
Map(m => m.ManufacturerNr).Name("Manufactorer number");
Map(m => m.RoHS).Name("RoHS");
Map(m => m.Nachweis).Name("Nachweis");
}
}
PartsPerList.cs:
public class PartsPerList
{
public string Listname { get; set; } = string.Empty;
}
ManufacturersPartsMap.cs:
public class ManufacturerPartsMap : ClassMap<PartsPerList>
{
public ManufacturerPartsMap()
{
Map(m => m.Listname).Name("test").Optional();
}
}
To write two different objects in one row with CSVHelper, you can loop through the records and write them line by line.
void Main()
{
var fooRecords = new List<Foo>
{
new Foo { Id = 1, Name = "one" },
new Foo { Id = 2, Name = "two" },
};
var barRecords = new List<Bar>
{
new Bar { Id = 3, Description = "The first one" },
new Bar { Id = 4, Description = "The secord one" },
};
//using (var writer = new StreamWriter("path\\to\\file.csv"))
using (var csv = new CsvWriter(Console.Out, CultureInfo.InvariantCulture))
{
csv.WriteHeader<Foo>();
csv.WriteHeader<Bar>();
csv.NextRecord();
for (int i = 0; i < fooRecords.Count; i++)
{
csv.WriteRecord(fooRecords[i]);
csv.WriteRecord(barRecords[i]);
csv.NextRecord();
}
}
}
public class Foo
{
[Name("FooId")]
public int Id { get; set; }
public string Name { get; set; }
}
public class Bar
{
[Name("BarId")]
public int Id { get; set; }
public string Description { get; set; }
}
Related
I am new to C# and OOP, in general, I've kinda hit a wall I am reading in this CSV using the CSV Helper package, but there are some unwanted rows, etc so I have cleaned it up by iterating over "records" and creating a new class LineItems.
But Now I appear to be a bit stuck. I know void doesn't return anything and is a bit of a placeholder. But How can I access all the instances of LineItems outside of this function?
public void getMapper()
{
using (var StreamReader = new StreamReader(#"D:\Data\Projects\dictUnitMapper.csv"))
{
using (var CsvReader = new CsvReader(StreamReader, CultureInfo.InvariantCulture))
{
var records = CsvReader.GetRecords<varMapper>().ToList();
foreach (var item in records)
{
if (item.name != "#N/A" && item.priority != 0)
{
LineItems lineItem = new LineItems();
lineItem.variableName = item.Items;
lineItem.variableUnit = item.Unit;
lineItem.variableGrowthCheck = item.growth;
lineItem.variableAVGCheck = item.avg;
lineItem.variableSVCheck = item.svData;
lineItem.longName = item.name;
lineItem.priority = item.priority;
}
}
}
}
}
public class LineItems
{
public string variableName;
public string variableUnit;
public bool variableGrowthCheck;
public bool variableAVGCheck;
public bool variableSVCheck;
public string longName;
public int priority;
}
public class varMapper
{
public string Items { get; set; }
public string Unit { get; set; }
public bool growth { get; set; }
public bool avg { get; set; }
public bool svData { get; set; }
public string name { get; set; }
public int priority { get; set; }
}
You should write your method to return a list.
public List<LineItems> GetMapper()
{
using (var StreamReader = new StreamReader(#"D:\Data\Projects\dictUnitMapper.csv"))
{
using (var CsvReader = new CsvHelper.CsvReader(StreamReader, CultureInfo.InvariantCulture))
{
return
CsvReader
.GetRecords<varMapper>()
.Where(item => item.name != "#N/A")
.Where(item => item.priority != 0)
.Select(item => new LineItems()
{
variableName = item.Items,
variableUnit = item.Unit,
variableGrowthCheck = item.growth,
variableAVGCheck = item.avg,
variableSVCheck = item.svData,
longName = item.name,
priority = item.priority,
})
.ToList();
}
}
}
Here's an alternative syntax for building the return value:
return
(
from item in CsvReader.GetRecords<varMapper>()
where item.name != "#N/A"
where item.priority != 0
select new LineItems()
{
variableName = item.Items,
variableUnit = item.Unit,
variableGrowthCheck = item.growth,
variableAVGCheck = item.avg,
variableSVCheck = item.svData,
longName = item.name,
priority = item.priority,
}
).ToList();
If the header object has a prop set to 1 then it should map field type1 in the child to type in the destination. Otherwise it should use type2.
Bonus points if I can use IValueResolver to use type1 or type1extended if extended is filled.
Here is my minimum viable product/demo
using AutoMapper;
using AutoMapper.Configuration.Conventions;
using System;
using System.Collections.Generic;
namespace ConsoleAppAutoMapper
{
class Program
{
static void Main(string[] args)
{
var source = new SourceParent() {
Header = new SourceHeader() { Currency = 30, FileName = "testfile.txt", Type = 1 },
Rows = new List<SourceRow>() {
new SourceRow() { ID = 1, Amount1 = 100, Amount2 = 200 },
new SourceRow() { ID = 2, Amount1 = 101, Amount2 = 201 },
new SourceRow() { ID = 3, Amount1 = 102, Amount2 = 202 }
} };
var config = new MapperConfiguration(cfg => {
cfg.CreateMap<SourceParent, DestinationParent>();
cfg.CreateMap<SourceRow, DestinationRow>()
.ForMember(x => x.Type, opt => opt.MapFrom(p => p.Type1));
});
var mapper = config.CreateMapper();
var dest = mapper.Map<DestinationParent>(source);
Console.WriteLine(dest.Rows[0].Type == 100); // should be true if SourceHeader.Type = 1 and should be 200 (SourceRow.Type2) if SourceHeader.Type = 2
Console.ReadKey();
}
}
// source
public class SourceParent
{
public SourceHeader Header { get; set; }
public List<SourceRow> Rows { get; set; }
}
public class SourceHeader
{
public string FileName { get; set; }
public int Type { get; set; }
}
public class SourceRow
{
public int ID { get; set; }
public int Amount1 { get; set; }
public int Amount2 { get; set; }
}
//destination
public class DestinationParent
{
public DestinationHeader Header { get; set; }
public List<DestinationRow> Rows { get; set; }
}
public class DestinationHeader
{
public string FileName { get; set; }
}
public class DestinationRow
{
public int ID { get; set; }
public int Type { get; set; }
public int Amount{ get; set; } // if type=1 then source is amount1 otherwise amount2
}
}
edit
I tried to solve it by having an Aftermap on the sourceparent mapping which took the value from the header and put it in a prop from the destinationrow (it is the Type value) and wanted another aftermap on the row to see if I needed prop A or B (type1 or type2) but that aftermap still does not know (it's null) what type it is because it happens before the aftermap of the parent it seems.
public class MapRowType : IMappingAction<SourceParent, DestinationParent>
{
public void Process(SourceParentsource, DestinationParent destination)
{
foreach (var row in destination.Rows)
{
row.Type = source.Header.Type; // so now I have type in the row, but still do not know if I should use Amount1 or Amount2
}
}
}
you can use the resolution context. Declare the mapping:
cfg.CreateMap<SourceRow, DestinationRow>()
.ForMember(x => x.Type,
opt => opt.ResolveUsing((src, dest1, destMember, resContext) => resContext.Items["Type"] as int? == 1? src.Type2: src.Type1));
After pass the value:
var dest = mapper.Map<DestinationParent>(source, opts=> { opts.Items["Type"] = source.Header.Type;});
I have s Student class where each student record has a list of Results.
I need to export there results to CSV and I'm using CsvHelper.
public class Student
{
public string Id { get; set; }
public string Name { get; set; }
public Result[] Grades { get; set; }
}
public class Result
{
public string Subject { get; set; }
public decimal? Marks { get; set; }
}
I'm using Reference Maps to map the list of Results, but when exporting to CSV it throws and error.
Mapping Code
public sealed class StudentResultExportMap : ClassMap<Student>
{
public StudentResultExportMap ()
{
AutoMap();
References<GradesMap>(m => m.Grades);
}
}
public sealed class GradesMap: ClassMap<Result>
{
public GradesMap()
{
Map(m => m.Subject);
Map(m => m.Marks);
}
}
Error
Property 'System.String Subject' is not defined for type
'{namespace}.GetStudentResults+Result[]' Parameter name: property
Unfortunately References<GradesMap>(m => m.Grades); doesn't work for an array of Result. It would work for an individual result. I have one solution, which overrides the ToString() method of Result to flatten the grades. It might work for you, depending on what you need.
public class Result
{
public string Subject { get; set; }
public decimal? Marks { get; set; }
public override string ToString()
{
return $"{Subject} = {Marks}";
}
}
Make a slight change to your StudentResultExportMap. You can set the 2nd number on .Index(2, 7) to handle the max number of grades you think a student might have.
public sealed class StudentResultExportMap : ClassMap<Student>
{
public StudentResultExportMap()
{
AutoMap();
Map(m => m.Grades).Name("Grade").Index(2, 7);
}
}
You will then get Id, Name, Grade1, Grade2, Grade3, Grade4, Grade5, Grade6 with the toString() value of Result for each grade.
var records = new List<Student>
{
new Student{ Id = "1", Name = "First", Grades = new [] {
new Result { Subject = "Subject1", Marks = (decimal)2.5 } ,
new Result { Subject = "Subject2", Marks = (decimal)3.5 } }},
new Student{ Id = "2", Name = "Second", Grades = new [] {
new Result { Subject = "Subject1", Marks = (decimal)3.5 } ,
new Result { Subject = "Subject2", Marks = (decimal)4.0 } }}
};
using (var writer = new StreamWriter("path\\to\\StudentResults.csv"))
using (var csv = new CsvWriter(writer))
{
csv.Configuration.RegisterClassMap<StudentResultExportMap>();
csv.WriteRecords(records);
}
All I want to do is return multiple reader.cast<> so that i can use 2 sqlcommands.
var first =reader.Cast<IDataRecord>().Select(x => new LocationInfo()
{
Names = x.GetString(0),
Values = Math.Round(x.GetDouble(1), 2).ToString("#,##0.00"),
ValuesDouble = x.GetDouble(1)
}).ToList();
reader.NextResult();
var second=reader.Cast<IDataRecord>().Select(x => new LocationInfo()
{
Names2 = x.GetString(0),
Values2 = Math.Round(x.GetDouble(1), 2).ToString("#,##0.00"),
ValuesDouble2 = x.GetDouble(1)
}).ToList();
All I want to do is return var first and var second. Please help :(
I'm using this Location.cs for parameters:
namespace MVCRealtime
{
public class LocationInfo
{
public string Names { get; set; }
public string Values { get; set; }
public double ValuesDouble { get; set; }
public string Names2 { get; set; }
public string Values2 { get; set; }
public double ValuesDouble2 { get; set; }
}
}
public static class ReaderHelper
{
public static IEnumerable<TElem> GetData<TElem>(this IDataReader reader, Func<IDataRecord, TElem> buildObjectDelegat)
{
while (reader.Read())
{
yield return buildObjectDelegat(reader);
}
}
}
// ...
var result = reader.GetData(x => new LocationInfo()
{
Names = x.GetString(0),
Values = Math.Round(x.GetDouble(1), 2).ToString("#,##0.00"),
ValuesDouble = x.GetDouble(1)
}).Take(2);
So you get 1st var in 1st element of the result and 2nd var in 2nd element.
here is example on how to store cross-referenced entities in LiteDB. LiteDB stores the cross-referenced entities perfectly fine, but problem comes when I am trying to find/load entities back. My goal is NOT ONLY the requested entity but also referenced ones. There is quick tutorial section "DbRef for cross references" on LiteDB webpage how one can realize it. LiteDB has "Include" option (which is called before "FindAll") which says which referenced entities must be loaded as well. I am trying to achieve it in this code example but with no results, i.e, the code raises Exception("D_Ref") meaning "D_Ref" reference is not loaded:
namespace _01_simple {
using System;
using LiteDB;
public class A {
public int Id { set; get; }
public string Name { set; get; }
public B B_Ref { set; get; }
}
public class B {
public int Id { set; get; }
public string Name { set; get; }
public C C_Ref { set; get; }
}
public class C {
public int Id { set; get; }
public string Name { set; get; }
public D D_Ref { set; get; }
}
public class D {
public int Id { set; get; }
public string Name { set; get; }
}
class Program {
static void Main(string[] args) {
test_01();
}
static string NameInDb<T>() {
var name = typeof(T).Name + "s";
return name;
}
static void test_01() {
if (System.IO.File.Exists(#"MyData.db"))
System.IO.File.Delete(#"MyData.db");
using (var db = new LiteDatabase(#"MyData.db")) {
var As = db.GetCollection<A>(NameInDb<A>());
var Bs = db.GetCollection<B>(NameInDb<B>());
var Cs = db.GetCollection<C>(NameInDb<C>());
var Ds = db.GetCollection<D>(NameInDb<D>());
LiteDB.BsonMapper.Global.Entity<A>().DbRef(x => x.B_Ref, NameInDb<B>());
LiteDB.BsonMapper.Global.Entity<B>().DbRef(x => x.C_Ref, NameInDb<C>());
LiteDB.BsonMapper.Global.Entity<C>().DbRef(x => x.D_Ref, NameInDb<D>());
var d = new D { Name = "I am D." };
var c = new C { Name = "I am C.", D_Ref = d };
var b = new B { Name = "I am B.", C_Ref = c };
var a = new A { Name = "I am A.", B_Ref = b };
Ds.Insert(d);
Cs.Insert(c);
Bs.Insert(b);
As.Insert(a);
}
using (var db = new LiteDatabase(#"MyData.db")) {
var As = db.GetCollection<A>(NameInDb<A>());
var all_a = As
.Include(x => x.B_Ref)
.FindAll();
foreach (var a in all_a) {
if (a.B_Ref == null)
throw new Exception("B_Ref");
if (a.B_Ref.C_Ref == null)
throw new Exception("C_Ref");
if (a.B_Ref.C_Ref.D_Ref == null)
throw new Exception("D_Ref");
}
}
}
}}
after small research I've resolved the issue simply by adding extra "Include" parameterize by "x => x.B_Ref.C_Ref" lambda where x.B_Ref.C_Ref is a path in hierarchy of references:
var all_a = As
.Include(x => x.B_Ref)
.Include(x => x.B_Ref.C_Ref)
.FindAll();
Here is complete example
namespace _01_simple {
using System;
using LiteDB;
public class A {
public int Id { set; get; }
public string Name { set; get; }
public B B_Ref { set; get; }
}
public class B {
public int Id { set; get; }
public string Name { set; get; }
public C C_Ref { set; get; }
}
public class C {
public int Id { set; get; }
public string Name { set; get; }
public D D_Ref { set; get; }
}
public class D {
public int Id { set; get; }
public string Name { set; get; }
}
class Program {
static void Main(string[] args) {
test_01();
}
static string NameInDb<T>() {
var name = typeof(T).Name + "s";
return name;
}
static void test_01() {
if (System.IO.File.Exists(#"MyData.db"))
System.IO.File.Delete(#"MyData.db");
using (var db = new LiteDatabase(#"MyData.db")) {
var As = db.GetCollection<A>(NameInDb<A>());
var Bs = db.GetCollection<B>(NameInDb<B>());
var Cs = db.GetCollection<C>(NameInDb<C>());
var Ds = db.GetCollection<D>(NameInDb<D>());
LiteDB.BsonMapper.Global.Entity<A>().DbRef(x => x.B_Ref, NameInDb<B>());
LiteDB.BsonMapper.Global.Entity<B>().DbRef(x => x.C_Ref, NameInDb<C>());
LiteDB.BsonMapper.Global.Entity<C>().DbRef(x => x.D_Ref, NameInDb<D>());
var d = new D { Name = "I am D." };
var c = new C { Name = "I am C.", D_Ref = d };
var b = new B { Name = "I am B.", C_Ref = c };
var a = new A { Name = "I am A.", B_Ref = b };
Ds.Insert(d);
Cs.Insert(c);
Bs.Insert(b);
As.Insert(a);
}
using (var db = new LiteDatabase(#"MyData.db")) {
var As = db.GetCollection<A>(NameInDb<A>());
var all_a = As
.Include(x => x.B_Ref)
.Include(x => x.B_Ref.C_Ref)
.Include(x => x.B_Ref.C_Ref.D_Ref)
.FindAll();
foreach (var a in all_a) {
if (a.B_Ref == null)
throw new Exception("B_Ref");
if (a.B_Ref.C_Ref == null)
throw new Exception("C_Ref");
if (a.B_Ref.C_Ref.D_Ref == null)
throw new Exception("D_Ref");
}
}
}
}}
I hope it saves someone's time.
Update: LiteDB author says there is no support for Cascading Include. But it is planned in the next version (see issue). Consider, once, let say, B_Ref is a Lite of B, then there is no mechanism to force deeper Include.