将多个列表加载到一个数据表中

Question

Hi I have two lists one is parent list and other one is child list And I need to load the data contain in both list to single Datatable is there are way to do that

public class Country
{
  string Name;
  string Countrycode
  list<Company> Companies=new list<Company>(); 
}

public class Company
{
  string ComapnyName;
  string Address1;
  string Address2;
  String Owner; 
} 

when creating table it must be like this

Name       Countrycode  ComapnyName   Address1    Address2   Owner              
USA          001          Apple       Whereever   null       Jobbs  
Japan        002          Sony        Whereever   null       unknown

Answer 1

What's the problem? You can use a loop:

DataTable tblCountries = new DataTable();
// add all columns ...
foreach(Country c in allCountries)
{
    if(c.Companies.Any())
    {
        foreach(var company in c.Companies)
        {
            var row = tblCountries.Rows.Add();
            row.SetField("Name", c.Name);
            row.SetField("Countrycode", c.Countrycode);
            row.SetField("CompanyName", company.CompanyName);
            // add the other company fields ...
        }
    }
    else  // add just the country and let the company cells be null
    {
        var row = tblCountries.Rows.Add();
        row.SetField("Name", c.Name);
        row.SetField("Countrycode", c.Countrycode);
    }
}

Answer 2

You probably want to use microsofts example of how to create a copy to datable method show here MSDN

You can then do the following

Country.SelectMany(x => x.Companies
                         .Select(y => new { 
                                            x.Name,
                                            x.CountryCode,
                                            y.ComapnyName,
                                            y.Address1,
                                            y.Address2,
                                            y.Owner
                                          } )).CopyToDataTable();

PS copied the spelling of Comapny name not sure if you mean this!

Update to deal with Companies being null

If the companies property could be null:

Country.SelectMany(x => (x.Companies ?? Enumerable.Empty<Company>())
                         .Select(y => new { 
                                            x.Name,
                                            x.CountryCode,
                                            y.ComapnyName,
                                            y.Address1,
                                            y.Address2,
                                            y.Owner
                                          } )).CopyToDataTable();