A blog about software development and whatever else I find interesting.
"((\d\d\d\d)-(\d\d)-(\d\d))T((\d\d):(\d\d):(\d\d))Z"Imagine that someone used the above regular expression on the following string.
"This is a UTC date : 1999-12-31T23:59:59Z. Get ready to party!"The very first group (after the matched date/time string) will be the entire date, because the first set of parentheses completely wraps the date portion of the string.
"1999-12-31"The next group would be the year portion of the date, since the next set of parentheses completely wraps the year.
"1999"That pattern is repeated for the rest of the regular expression string. If no parentheses (groupings) are specified, then there will only be the one group and it will contain the string that the regular expression matched. Here is an example of how to do this in code:
static void Main(string[] args)
{
string input = "this\tis\ta test 2013-03-21T12:34:56Z\tand\tanother date\t2013-03-21T23:45:01Z";
string regexString = @"((\d\d\d\d)-(\d\d)-(\d\d))T((\d\d):(\d\d):(\d\d))Z";
TestRegex(input, regexString);
}
private static void TestRegex(string input, string regexString)
{
int matchCount = 0;
foreach (Match match in Regex.Matches(input, regexString))
{
int groupCount = 0;
foreach (Group group in match.Groups)
{
Console.WriteLine("Match {0}, Group {1} : {2}",
matchCount,
groupCount++,
group.Value);
}
matchCount++;
}
}
Here is the output:
Match 0, Group 0 : 2013-03-21T12:34:56Z Match 0, Group 1 : 2013-03-21 Match 0, Group 2 : 2013 Match 0, Group 3 : 03 Match 0, Group 4 : 21 Match 0, Group 5 : 12:34:56 Match 0, Group 6 : 12 Match 0, Group 7 : 34 Match 0, Group 8 : 56 Match 1, Group 0 : 2013-03-21T23:45:01Z Match 1, Group 1 : 2013-03-21 Match 1, Group 2 : 2013 Match 1, Group 3 : 03 Match 1, Group 4 : 21 Match 1, Group 5 : 23:45:01 Match 1, Group 6 : 23 Match 1, Group 7 : 45 Match 1, Group 8 : 01
string key = "theawskeythatyougetwhenyousignuptousetheapis";
string secretKey = "thesecretkeyyougetwhenyousignuptousetheapis";
// create an instance of the S3 TransferUtility using the API key, and the secret key
var tu = new TransferUtility(key, secretKey);
// try listing any buckets you might have
var response = tu.S3Client.ListBuckets();
foreach(var bucket in response.Buckets)
{
Console.WriteLine("{0} - {1}", bucket.BucketName, bucket.CreationDate);
// list any objects that might be in the buckets
var objResponse = tu.S3Client.ListObjects(
new ListObjectsRequest
{
BucketName = response.Buckets[0].BucketName
}
);
foreach (var s3obj in objResponse.S3Objects)
{
Console.WriteLine("\t{0} - {1} - {2} - {3}", s3obj.ETag, s3obj.Key, s3obj.Size, s3obj.StorageClass);
}
}
// create a new bucket
string bucketName = Guid.NewGuid().ToString();
var bucketResponse = tu.S3Client.PutBucket(new PutBucketRequest
{
BucketName = bucketName
}
);
// add something to the new bucket
tu.S3Client.PutObject(new PutObjectRequest
{
BucketName = bucketName,
AutoCloseStream = true,
Key = "codecog.png",
FilePath = "C:\\Temp\\codecog.png"
}
);
// now list what is in the new bucket (which should only have the one item)
var bucketObjResponse = tu.S3Client.ListObjects(
new ListObjectsRequest
{
BucketName = bucketName
}
);
foreach (var s3obj in bucketObjResponse.S3Objects)
{
Console.WriteLine("{0} - {1} - {2} - {3}", s3obj.ETag, s3obj.Key, s3obj.Size, s3obj.StorageClass);
}
Important configurations
- IgnoreIfAutoMapFails - Calling this prevents automapper from throwing an exception if a column cannot be mapped to a corresponding property due to a name mismatch.
create table if not exists `authors` ( `authorid` int not null auto_increment, `firstname` varchar(100) not null, `middlename` varchar(100), `lastname` varchar(100) not null, primary key (`authorid` asc) ); create table if not exists `books` ( `bookid` int not null auto_increment, `title` varchar(200) not null, `authorid` int, `isbn` varchar(30), primary key (`bookid` asc) );
public class Author
{
public int AuthorID { get; set; }
public string FirstName { get; set; }
public string MiddleName { get; set; }
public string LastName { get; set; }
public string ToString()
{
if (string.IsNullOrEmpty(MiddleName))
{
return string.Format("{0} - {1} {2}", AuthorID, FirstName, LastName);
}
return string.Format("{0} - {1} {2} {3}", AuthorID, FirstName, MiddleName, LastName);
}
}
public class Book
{
public int BookID { get; set; }
public string Title { get; set; }
public string ISBN { get; set; }
public Author Author { get; set; }
public string ToString()
{
if (Author != null)
{
return string.Format("{0} - {1} \n\t({2} - {3})", BookID, Title, ISBN, Author.ToString());
}
return string.Format("{0} - {1} \n\t({2})", BookID, Title, ISBN);
}
}
I was then able to populate a list of books by selecting rows from the books table:
public static void PrintBooks()
{
IDbContext dbcontext = new DbContext().ConnectionStringName("mysql-inventory", new MySqlProvider());
const string sql = @"select b.bookid, b.title, b.isbn
from books as b;";
List<Book> books = dbcontext.Sql(sql).QueryMany<Book>();
Console.WriteLine("Books");
Console.WriteLine("------------------");
foreach (Book book in books)
{
Console.WriteLine(book.ToString());
}
}
Unfortunately I wasn't able to select columns from the table that didn't have matching attributes in the entity type. You'll need to create a custom mapping method in order to select extra columns that don't map to any attributes in the entity type. You can also use custom mapping methods to populate entity types that contain attributes of other entity types).
public static void PrintBooksWithAuthors()
{
IDbContext dbcontext = new DbContext().ConnectionStringName("mysql-inventory", new MySqlProvider());
const string sql = @"select b.bookid, b.title, b.isbn, b.authorid, a.firstname, a.middlename, a.lastname, a.authorid
from authors as a
inner join books as b
on b.authorid = a.authorid
order by b.title asc, a.lastname asc;";
var books = new List<Book>();
dbcontext.Sql(sql).QueryComplexMany<Book>(books, MapComplexBook);
Console.WriteLine("Books with Authors");
Console.WriteLine("------------------");
foreach (Book book in books)
{
Console.WriteLine(book.ToString());
}
}
private static void MapComplexBook(IList<Book> books, IDataReader reader)
{
var book = new Book
{
BookID = reader.GetInt32("BookID"),
Title = reader.GetString("Title"),
ISBN = reader.GetString("ISBN"),
Author = new Author
{
AuthorID = reader.GetInt32("AuthorID"),
FirstName = reader.GetString("FirstName"),
MiddleName = reader.GetString("MiddleName"),
LastName = reader.GetString("LastName")
}
};
books.Add(book);
}
public static void InsertBook(string title, string ISBN)
{
IDbContext dbcontext = new DbContext().ConnectionStringName("mysql-inventory", new MySqlProvider());
Book book = new Book
{
Title = title,
ISBN = ISBN
};
book.BookID = dbcontext.Insert("books")
.Column("Title", book.Title)
.Column("ISBN", book.ISBN)
.ExecuteReturnLastId<int>();
Console.WriteLine("Book ID : {0}", book.BookID);
}
public static void UpdateBook(Book book)
{
IDbContext dbcontext = new DbContext().ConnectionStringName("mysql-inventory", new MySqlProvider());
book.Title = string.Format("new - {0}", book.Title);
int rowsAffected = dbcontext.Update("books")
.Column("Title", book.Title)
.Where("BookId", book.BookID)
.Execute();
Console.WriteLine("{0} rows updated.", rowsAffected);
}
public static void DeleteBook(Book book)
{
IDbContext dbcontext = new DbContext().ConnectionStringName("mysql-inventory", new MySqlProvider());
int rowsAffected = dbcontext.Delete("books")
.Where("BookId", book.BookID)
.Execute();
Console.WriteLine("{0} rows deleted.", rowsAffected);
}
private const string pooled =
@"Data Source=someserver;Initial Catalog=dbname;Integrated Security=SSPI;";
private const string notpooled =
@"Data Source=someserver;Initial Catalog=dbname;Integrated Security=SSPI;Pooling=false;";
public static void Main(string[] args)
{
int testCount = 10000;
GenericDatabase db = new GenericDatabase(pooled, SqlClientFactory.Instance);
Console.WriteLine(" pooled : {0}", RunConnectionTest(db, testCount));
db = new GenericDatabase(notpooled, SqlClientFactory.Instance);
Console.WriteLine("not pooled : {0}", RunConnectionTest(db, testCount));
}
private static TimeSpan RunConnectionTest(GenericDatabase db, int testCount)
{
Stopwatch sw = new Stopwatch();
sw.Start();
DbConnection conn;
for (int i = 0; i < testCount; i++)
{
conn = db.CreateConnection();
conn.Open();
var schema = conn.GetSchema(); // just to make the code do something
conn.Close();
}
sw.Stop();
return sw.Elapsed;
}
When connection pooling is enabled, and if a timeout error or other login error occurs, an exception will be thrown and subsequent connection attempts will fail for the next five seconds, the "blocking period". If the application attempts to connect within the blocking period, the first exception will be thrown again. After the blocking period ends, another connection failure by the application will result in a blocking period that is twice as long as the previous blocking period. Subsequent failures after a blocking period ends will result in a new blocking periods that is twice as long as the previous blocking period, up to a maximum of five minutes.So, if the mysterious SQL connection issue is causing a connection to fail, then we should expect exponentially longer waits (up to 5 minutes) for each failure to connect. It would explain why our web method call is taking hardly any time to return usually, and then takes 30+ seconds at other times.
The specified service has been marked for deletionI won't be able to install the service until the service is uninstalled, and Windows won't uninstall the service until the machine is rebooted. I tried the "sc delete <service name>" method for deleting a service, and I get the same message about the service being marked for deletion. I ended up rebooting, and the service was gone when Windows restarted.
List<int> list = new List<int>();