SqlParameter is already contained by another SqlParameterCollection, but I don't see how

Question

I have the following code.

// Get total row count and build Pagination object
var countQuery = ArticleServerContext.Database.SqlQuery<int>("GetFullTextSearchCount @SearchTerm",
    new SqlParameter("@SearchTerm", fullTextQuery));
Pagination pagination = new Pagination(countQuery.Single(), page ?? 1);
// Get search results for current page
var resultsQuery = ArticleServerContext.Database.SqlQuery<ArticleSummary>("GetFullTextSearchResults @SearchTerm, @SkipRows, @TakeRows",
    new SqlParameter("@SearchTerm", fullTextQuery),
    new SqlParameter("@SkipRows", pagination.SkippedRows),
    new SqlParameter("@TakeRows", pagination.RowsPerPage));
// Build model
SearchResultsModel model = new SearchResultsModel
{
    SearchTerm = searchTerm.Trim(),
    Pagination = pagination,
    Results = resultsQuery.ToList()   // <=== Here's where the error happens
};

When I attempt to enumerate resultsQuery, I get the following error message.

The SqlParameter is already contained by another SqlParameterCollection.

This error message seems clear enough, but I cannot see where I'm adding an SqlParameter to more than one anything. The only thing I can imagine is that the first parameter to both calls are identical. Could C# be combining them somehow? Either way, I need them to contain the same data.

Can anyone see what's happening here?

EDIT:

Sorry, this turned out to be a debugging issue. I had another issue that prevented the results I expected. But when I break in the debugger and step through my code, I get the error mentioned above.

It seems that the code executes using the SqlParameter in question, and then I attempt to inspect the contents of the query and the query runs again with the same SqlParameter, and that is what is causing the error.

Unfortunately, now that I have a bounty, I cannot delete the question.

Answer 1

I didn't have a good understanding of what was happening when I posted this question. After further study, it turns out that:

1. A separate issue was causing my program not to display the (any) results I expected.

2. Using the Visual Studio debugger, I had set a breakpoint in this code. As I stepped through, the queries were being executed. But then when I attempt to inspect the data, that caused the queries to be executed again. It was this dual execution that was causing the error I reported. In fact, this error was not occurring when the code ran normally.

Thanks to everyone who took time to look at this issue.