I have a Linq to Entities query and I want to select some specific columns and store the new object into a pre-defined object. However, I'm getting the error
<object>
does not contain a constructor that takes 0 arguments.
Not sure what is wrong here...
Also not sure if this is the best way or if using anonymous type is better instead of creating a payroll object.
Linq Query
public Payroll GetTestCasePayroll(decimal testScenarioID) //not sure if object is correct return
{
Payroll instance = (from o in DbContext.UI_OnDemandCheckHeader
where o.TestScenarioID == testScenarioID
select new Payroll(o.PayEntityCode, o.PayrollYear, o.PayrollNumber)).First();
//{ PayEntityCode = , PayrollYear = o.PayrollYear, PayrollNumber = o.PayrollNumber }).First();
return instance;
}
Payroll object
class Payroll
{
private string _payEntityCode;
private decimal _payrollYear;
private string _payrollNumber;
public Payroll(string payEntityCode, decimal payrollYear, string payrollNumber)
{
PayEntityCode = payEntityCode;
PayrollYear = payrollYear;
PayrollNumber = payrollNumber;
}
public decimal PayrollYear
{
get { return _payrollYear; }
set { _payrollYear = value; }
}
public string PayEntityCode
{
get { return _payEntityCode; }
set { _payEntityCode = value; }
}
public string PayrollNumber
{
get { return _payrollNumber; }
set { _payrollNumber = value; }
}
Your Payroll class needs a constructor that takes no parameters eg
Public Payroll() { }
Linq works by creating an empty instance of the output class and then using the setters on each of the properties. It does not use anything but an empty constructor.
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