Failed to convert parameter value from a list`1 to a ienumerable`1.

When you encounter the error “Failed to convert parameter value from a List<T> to an IEnumerable<T>”, it means there is a type mismatch between the parameter and the input data type.

The error occurs when you try to pass a List<T> (a generic list) as a parameter value, but the parameter type is defined as IEnumerable<T> (an enumerable).

To fix this error, you have a few options:

Option 1: Change the Parameter Type

  // Example 1: Method with IEnumerable<T> parameter
  public void MyMethod(IEnumerable<int> values)
  {
      // Method implementation...
  }

  // Example usage with a List<T>
  List<int> myList = new List<int>() { 1, 2, 3 };
  MyMethod(myList); // This will give the error

  // To fix the error, change the parameter type to List<T>
  public void MyMethod(List<int> values)
  {
      // Method implementation...
  }

  // Now the method can accept both List<T> and IEnumerable<T>
  MyMethod(myList); // No error
  

Option 2: Convert the List to IEnumerable

  // If you cannot change the parameter type, you can convert the List to IEnumerable using the Enumerable.ToList() method
  List<int> myList = new List<int>() { 1, 2, 3 };
  MyMethod(myList.ToList()); // This will fix the error
  

Option 3: Directly Use IEnumerable

  // If you have control over the method implementation, you can directly use IEnumerable instead of List in the method signature
  public void MyMethod(IEnumerable<int> values)
  {
      // Method implementation...
  }

  // Example usage with a List<T>
  List<int> myList = new List<int>() { 1, 2, 3 };
  MyMethod(myList); // No error
  

These are the options you have to fix the error “Failed to convert parameter value from a List<T> to an IEnumerable<T>”. Choose the option that suits your situation best.