// Construct get-request for first table
KeysAndAttributes sampleTableItems = new KeysAndAttributes();
sampleTableItems.WithAttributesToGet("Author", "Title", "Year");
sampleTableItems.WithKeys(
    new Key()
        .WithHashKeyElement(new AttributeValue().WithS("Mark Twain"))
        .WithRangeKeyElement(new AttributeValue().WithS("The Adventures of Tom Sawyer")),
    new Key()
        .WithHashKeyElement(new AttributeValue().WithS("Mark Twain"))
        .WithRangeKeyElement(new AttributeValue().WithS("Adventures of Huckleberry Finn"))
);

// Construct get-request for second table
KeysAndAttributes authorsTableItems = new KeysAndAttributes();
// Skip setting AttributesToGet property to retrieve all attributes
sampleTableItems.WithKeys(
    // AuthorsTable only has a hash-key, no range-key
    new Key().WithHashKeyElement(new AttributeValue().WithS("Mark Twain")),
    new Key().WithHashKeyElement(new AttributeValue().WithS("Booker Taliaferro Washington"))
);

// Create a client
AmazonDynamoDBClient client = new AmazonDynamoDBClient();

// Construct table-keys mapping
Dictionary<string, KeysAndAttributes> requestItems = new Dictionary<string, KeysAndAttributes>();
requestItems["SampleTable"] = sampleTableItems;
requestItems["AuthorsTable"] = authorsTableItems;

// Construct request
BatchGetItemRequest request = new BatchGetItemRequest
{
    RequestItems = requestItems
};

BatchGetItemResult result;
do
{
    // Issue request and retrieve items
    result = client.BatchGetItem(request).BatchGetItemResult;

    // Iterate through responses
    Dictionary<string, BatchResponse> responses = result.Responses;
    foreach (string tableName in responses.Keys)
    {
        // Get items for each table
        BatchResponse tableItems = responses[tableName];

        // View items
        List<Dictionary<string, AttributeValue>> items = tableItems.Items;
        foreach (Dictionary<string, AttributeValue> item in items)
        {
            Console.WriteLine("Item:");
            foreach (var keyValuePair in item)
            {
                Console.WriteLine("{0} : S={1}, N={2}, SS=[{3}], NS=[{4}]",
                    keyValuePair.Key,
                    keyValuePair.Value.S,
                    keyValuePair.Value.N,
                    string.Join(", ", keyValuePair.Value.SS.ToArray()),
                    string.Join(", ", keyValuePair.Value.SS.ToArray()));
            }
        }
    }

    // Some items may not have been retrieved!
    //  Set RequestItems to the result's UnprocessedKeys and reissue request
    request.RequestItems = result.UnprocessedKeys;

} while (result.UnprocessedKeys.Count > 0);