Cannot implicitly convert type ‘System.Collections.Generic.List< >‘ to ‘System.Collections.Generic.IList< >‘

Assuming InvoiceMaster derives from or implements InvoiceHD, and that you’re using C# 4 and .NET 4 or higher, you can just use generic variance:

return MstDtl.ToList<InvoiceHD>();

This uses the fact that an IEnumerable<InvoiceMaster> is an IEnumerable<InvoiceHD> because IEnumerable<T> is covariant in T.

Another way to solve it would be to change the declaration of MstDtl to use explicit typing:

IEnumerable<InvoiceMaster> MstDtl = ...;

(I’d also suggest following regular C# naming, where local variables start with a lower-case letter, but that’s a different matter.)

Related Posts:

  1. Group by in LINQ
  2. Join/Where with LINQ and Lambda
  3. LINQ’s Distinct() on a particular property
  4. Sequence contains no elements?
  5. LEFT OUTER JOIN in LINQ
  6. ToList().ForEach in Linq
  7. Extension methods must be defined in a non-generic static class
  8. Proper Linq where clauses
  9. Extension methods must be defined in a non-generic static class
  10. Select distinct using linq
  11. Convert Linq Query Result to Dictionary
  12. Get single value from dictionary by key
  13. IEnumerable vs List – What to Use? How do they work?
  14. Sequence contains no matching element
  15. Linq select objects in list where exists IN (A,B,C)
  16. How do I concatenate two arrays in C#?
  17. Convert SQL to LINQ Query
  18. Sequence contains more than one element
  19. Quickest way to compare two generic lists for differences
  20. LINQ query on a DataTable
  21. Using .Select and .Where in a single LINQ statement
  22. Linq: GroupBy, Sum and Count
  23. How can I convert String to Int?
  24. CS0120: An object reference is required for the nonstatic field, method, or property ‘foo’
  25. How to find child of a GameObject or the script attached to child GameObject via script
  26. Process cannot access the file because it is being used by another proess
  27. How to convert JSON to XML or XML to JSON?
  28. Virustotal Trapmine suspicious.low.ml.score
  29. Convert int to string?
  30. Unity OnTriggerEnter2D not registering
  31. How to Sort a List by a property in the object
  32. The page was not displayed because the request entity is too large on IIS
  33. C# An established connection was aborted by the software in your host machine
  34. Multiple Inheritance in C#
  35. Return multiple values to a method caller
  36. Regex that accepts only numbers (0-9) and NO characters
  37. How to resolve this System.IO.FileNotFoundException
  38. Fire ontextchanged() event of an asp:TextBox via Javascript
  39. C# Gridview CheckBox Field VS (Template Field + CheckBox)
  40. Convert char to int in C#
  41. SmtpException: Unable to read data from the transport connection: net_io_connectionclosed
  42. The remote server returned an error: (403) Forbidden
  43. How can I get the application’s path in a .NET console application?
  44. How to add a delay for a 2 or 3 seconds
  45. Multiple file-extensions searchPattern for System.IO.Directory.GetFiles
  46. calling javascript function on OnClientClick event of a Submit button
  47. C# – Illegal characters in path
  48. Getting The ASCII Value of a character in a C# string
  49. Process exists with ExitCode 255
  50. The data types text and varchar are incompatible in the equal to operator in C#
  51. Name does not exist in the current context
  52. Unable to read data from the transport connection : An existing connection was forcibly closed by the remote host
  53. Member ‘‘ cannot be accessed with an instance reference
  54. The remote server returned an error: (407) Proxy Authentication Required
  55. when do you need .ascx files and how would you use them?
  56. IsNumeric function in c#
  57. How to open a new form from another form
  58. C# – How to convert string to char?
  59. The calling thread must be STA, because many UI components require this in WPF
  60. Error when Building Project: Error building Player because scripts have compile errors in the editor
  61. Unity3D. Trying to send command for object without authority
  62. The type initializer for ‘MyClass’ threw an exception
  63. The server committed a protocol violation. Section=ResponseStatusLine ERROR
  64. Specified cast is not valid.. how to resolve this
  65. C# switch on type
  66. How to post JSON to a server using C#?
  67. C# Error (Cannot Implicitly convert type ‘string’ to ‘int’)
  68. .NET graph library around?
  69. EF CodeFirst: Either the parameter @objname is ambiguous or the claimed @objtype (COLUMN) is wrong
  70. Input string was not in a correct format
  71. How can I cast int to enum?
  72. What is the C# equivalent of friend?
  73. How to get relative path of a file in visual studio?
  74. Error Message: Type or namespace definition, or end-of-file expected
  75. Make first letter of a string upper case (with maximum performance)
  76. How can I wait for a thread to finish with .NET?
  77. How to add a new row to datagridview programmatically
  78. Unexpected character encountered while parsing value
  79. How do I exit a WPF application programmatically?
  80. OnCollisionEnter is not called in unity
  81. The name ‘ViewBag’ does not exist in the current context – Visual Studio 2015
  82. How to create a new object instance from a Type
  83. Cannot drop database because it is currently in use
  84. Troubleshooting “program does not contain a static ‘Main’ method” when it clearly does…?
  85. does not implement interface member
  86. Unity 5.2.2 changing Visual Studio back to MonoDevelop
  87. Differences between SFTP and “FTP over SSH”
  88. When should I use a List vs a LinkedList
  89. Remove punctuation from string with Regex
  90. Unity – How to stop Play Mode in case of infinite loop?
  91. Go To Definition: “Cannot navigate to the symbol under the caret.”
  92. Why am I getting an Exception with the message “Invalid setup on a non-virtual (overridable in VB) member…”?
  93. Is there a keyboard shortcut to maximize the Game window in Unity in Play Mode?
  94. IF Statement multiple conditions, same statement
  95. What is the easiest way to handle associative array in c#?
  96. What does the M stand for in C# Decimal literal notation?
  97. Iif equivalent in C#
  98. Convert an array to string
  99. is inaccessible due to its protection level
  100. Memory Leak caused by System.Drawing.Internal.GPStream

Leave a Comment

error code: 523