Get document from document set by caml query

Question

I have a requirement to fetch a single document from a document set. I have 5 different custom content types that have document set as the base type. Each document set has numerous documents. I want to get a particular document from the document set using a CAML query. Please guide.

Answer 1

This should work

var query = new SPQuery();
query.RowLimit = 1;
query.Folder = documentSet.Folder;
query.Query = string.Format("<Where><Eq><FieldRef Name='ContentType' /><Value Type='Computed'>{0}</Value></Eq></Where>", "ContentTypeName");
var items = documentSet.ParentList.GetItems(query);

Answer 2

I tried with the answer mentioned by Daniel but was unable to get the result. I have been able to get a file with a particular name from the document set by the following approach:

• Fetch all the items of the Document library
• Check whether the item is a document or not
• If it document set, check whether it has subfolders
• When is does not have sub folders, fetch the File you required from the document set.

Please refer the code given below, which shall give you a better clarity on what I am trying to explain.

//checks whether list item is document set or not.
    public bool IsDocumentSet(SPListItem item)
    {
        bool documentSetItem = false;
        DocumentSet documentSet = null;
        if (null != item && IsFolder(item))
        {
            documentSet = DocumentSet.GetDocumentSet(item.Folder);
            if (null != documentSet)
                documentSetItem = true;
        }
        return documentSetItem;
    }

    //checks whether list item contains folder
    public bool IsFolder(SPListItem item)
    {
        if (item.Folder != null)
        {
            return true;
        }
        else
        {
            return false;
        }

    }

      SPFile excelFile = null;
        SPListItemCollection collListItems = docList.Items;
        foreach (SPListItem oListItem in collListItems)
        {
            if (IsDocumentSet(oListItem))
            {
                SPFolder documentsetFolder = oListItem.Folder;
                if (documentsetFolder.Name.Equals("kevin"))
                {
                    SPFileCollection filecoll = documentsetFolder.Files;
                    foreach (SPFile tempfile in filecoll)
                    {
                        if (tempfile.Name.Contains("File name that you are looking for"))
                        {
                            excelFile = tempfile;
                        }
                    }
                }

            }
        }

docList is the SPList object of the document library that you are wanting to query.