dll<\/em>) <\/h3>\nTo create this project, you can simply take a "Class Library" <\/strong>project, while choosing from project wizard option. let’s name it "TransactionLib<\/strong><\/code>", it is the actual service which implements the business logic. The project already contains a file Class1.cs<\/em>, let us do some house keeping, before we write any code for the service library <\/p>\nLittle House Keeping<\/h4>\n\n- Delete the file <\/strong>Class1.cs<\/em> from the project workspace. <\/li>\n
- Add a new Interface<\/strong> named ICuboidService <\/strong>to the project, a new file ICuboidService.cs<\/strong> will be added to the project. <\/li>\n
- Add a new Class<\/strong> named CuboidService<\/strong>, to the project. that will implement the
ICuboidService<\/code> <\/strong>interface, a new file CuboidService.cs<\/em><\/strong> will be added to the project. <\/li>\n<\/ul>\nDefining ICuboidService Interface (ICuboidService.cs).<\/h4>\n
ICuboidService interface has seven methods, out of which<\/p>\n
\n- two methods with mandatory transactions as shown below. <\/li>\n<\/ul>\n
void AddTM<\/strong>(int nID, double dblL, double dblW, double dblH); <\/font><\/font><\/p>\n void UpdateTM<\/strong>(int nID, double dblL, double dblW, double dblH); <\/p>\n<\/font><\/font><\/p>\n
void DeleteTM<\/strong>(int nID);<\/font> <\/p>\n<\/font><\/p>\n
notice that, each method has been decorated with <\/p>\n
[TransactionFlow(TransactionFlowOption.Mandatory)]<\/font> <\/font><\/p>\nmandates<\/strong> the transaction flow, from the client. that says, that client must create a transaction <\/strong>and propagate its transaction to the service, before executing these methods. if these methods are called without transaction, an exception is generated<\/strong>. <\/p>\n[FaultContract(typeof(CuboidFaultException))]<\/font><\/p>\nimplements a FaultContract<\/strong>, which raises CuboidFaultException<\/strong>, if there is something not the way, as it supposed to be. <\/p>\n\n- the next two methods with allowed transactions as shown below. <\/li>\n<\/ul>\n
void AddTA<\/strong>(int nID, double dblL, double dblW, double dblH); <\/font><\/font><\/p>\n void UpdateTA<\/strong>(int nID, double dblL, double dblW, double dblH); <\/p>\n<\/font><\/font><\/p>\n
void DeleteTA<\/strong>(int nID);<\/font> <\/p>\n<\/font><\/p>\n
notice that, each method has been decorated with <\/p>\n
[TransactionFlow(TransactionFlowOption.Allowed)] <\/font><\/p>\nthat says, that client may create a transaction<\/strong> and propagate its transaction, to the service, before executing these methods. if client does not create a transaction, and method implementation is marked with, <\/p>\n[OperationBehavior(TransactionScopeRequired = true)]<\/font><\/p>\nthen service itself will create a transaction scope, to execute its method. <\/p>\n
[FaultContract(typeof(CuboidFaultException))]<\/font><\/p>\nimplements a FaultContract<\/strong>, which raises CuboidFaultException<\/strong>, if there is something not the way, as it supposed to be. <\/p>\n\n- the last method simply implements a fault contract, and does not mention anything about transaction, that means this method can be executed without any transaction overhead. <\/li>\n<\/ul>\n
[OperationContract]
\n
[FaultContract(typeof(CuboidFaultException))] <\/p>\nDictionary<int, CuboidData> GetList();<\/font><\/p>\n
Implement ICuboidService Interface (CuboidService.cs).<\/h4>\n
CuboidService class implements the ICuboidService interface, as shown below. Service has been decorated with some attributes.<\/p>\n
[ServiceBehavior(TransactionIsolationLevel = System.Transactions.IsolationLevel.Serializable)]
\n
public class CuboidService : ICuboidService <\/p>\n{<\/font> <\/p>\n
<\/font>The isolation level <\/strong>of a transaction determines what level of access other transactions have to volatile data before a transaction completes. The data affected by a transaction is called volatile. When you create a transaction, you can specify the isolation level that applies to the transaction. The isolation level of a transaction determines what level of access other transactions have to volatile data before a transaction completes. The highest isolation level, Serializable<\/strong>, provides a high degree of protection against interruptive transactions, but requires that each transaction complete before any other transactions are allowed to operate on the data. <\/p>\nMethod AddTM ( int nID, double dblL, double dblW, double dblH)<\/h5>\n
AddTM<\/strong> is used to Add data to the table, passed cuboid information its information is added to the CuboidInfo<\/strong> table, and its volume and surface area is calculated and added to the CuboidDetail<\/strong> table. <\/p>\n[OperationBehavior(TransactionScopeRequired = true, TransactionAutoComplete = true)]
\n
public void AddTM(int nID, double dblL, double dblW, double dblH) <\/p>\n{<\/font><\/p>\n
Operations are decorated with <\/p>\n
TransactionScopeRequired = true<\/strong>,<\/font> that simply says that this operation requires a TransactionScope<\/strong>, if client does not propagate its transaction, transaction is created at the service level itself.<\/p>\nTransactionAutoComplete = true<\/font><\/strong> signifies, to complete the transaction scope automatically on successful execution of the operation; <\/p>\nif ((nID <= 0) || (dblL <= 0) || (dblW <= 0) || (dblH <= 0))
\n
{ <\/p>\n CuboidFaultException faultEx = new CuboidFaultException(); <\/p>\n
faultEx.Reason = "Any dimension of Cuboid (length\/width\/height) can not be zero or negative value"; <\/p>\n
faultEx.Source = "AddUpdateTM"; <\/p>\n
StringBuilder sbDetail = new StringBuilder(""); <\/p>\n
if (nID <= 0) sbDetail.Append("[ID is <= 0] "); <\/p>\n
if (dblL <= 0) sbDetail.Append("[Length is <= 0] "); <\/p>\n
if (dblW <= 0) sbDetail.Append("[Width is <= 0] "); <\/p>\n
if (dblW <= 0) sbDetail.Append("[Height is <= 0]"); <\/p>\n
faultEx.Detail = sbDetail.ToString(); <\/p>\n
throw new FaultException<CuboidFaultException>(faultEx); <\/p>\n
} <\/p>\n
<\/font>then method checks the passed parameters, in case they are zero or negative a FaultException<\/strong> is thrown. if the input parameters are permissible, then usual business logic proceeds, that includes.<\/p>\n\n- calculating the values to be added\/updated in CuboidDetail table. <\/li>\n<\/ul>\n
double dblVolume = (dblL * dblW * dblH);
\n
double dblSArea = 2 * ((dblL * dblW) + (dblW * dblH) + (dblL * dblH));<\/font> <\/p>\n\n- preparing appropriate query to be run on database, for both the tables, according to the method called (add\/update). <\/li>\n<\/ul>\n
strQuery1 <\/strong>= "INSERT INTO CuboidInfo (ID, Length, Width, Height ) VALUES (" + nID.ToString() + ", " + dblL.ToString("F2") + ", " + dblW.ToString("F2") + ", " + dblH.ToString("F2") + " )"; <\/p>\n strQuery2 <\/strong>= "INSERT INTO CuboidDetail (ID, SurfaceArea, Volume) VALUES (" + nID.ToString() + ", " + dblSArea.ToString("F2") + ", " + dblVolume.ToString("F2") + " )";<\/font><\/p>\n\n- Reading Connection string from the App.config file of the host application. <\/li>\n<\/ul>\n
\/\/ Get the all keys from the appSettings section from the configuration file.
\n
System.Configuration.Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None); <\/p>\nAppSettingsSection appSettings = (AppSettingsSection)config.GetSection("appSettings"); <\/p>\n
string[] keys = appSettings.Settings.AllKeys;<\/font><\/p>\n
\/\/ Get the connection string.
\n
string strConnStr = appSettings.Settings["ConnectionString"].Value;<\/font><\/font><\/p>\n\n- Now the business logic, open Connection, execute both the queries, if there is any error throw a fault exception encapsulating error information. <\/li>\n<\/ul>\n
try
\n
{ <\/p>\n \/\/ Open Connection <\/p>\n
dbConn = new SqlConnection(strConnStr); <\/p>\n
dbConn.Open();<\/font><\/p>\n
\/\/ Create Command for Query 1
\n
SqlCommand dbCmd1 = new SqlCommand(strQuery1, dbConn); <\/p>\n nCnt1 = dbCmd1.ExecuteNonQuery();<\/font><\/p>\n
\/\/ Create Command for Query 2
\n
SqlCommand dbCmd2 = new SqlCommand(strQuery2, dbConn); <\/p>\n nCnt2 = dbCmd2.ExecuteNonQuery();<\/font><\/p>\n
\/\/ If TransactionAutoComplete=false, you need the line below.
\n
<\/strong> \/\/ OperationContext.Current.SetTransactionComplete(); <\/font><\/p>\n \/\/ Close Connection.
\n
dbConn.Close(); <\/p>\n dbConn = null; <\/p>\n
}<\/font><\/p>\n
catch (Exception eX)
\n
{ <\/p>\n \/\/ Close Connection. <\/p>\n
if (dbConn != null) <\/p>\n
{ <\/p>\n
if (dbConn.State == ConnectionState.Open) dbConn.Close(); <\/p>\n
dbConn = null; <\/p>\n
}<\/font><\/p>\n
CuboidFaultException faultEx = new CuboidFaultException();
\n
faultEx.Reason = "Failed while performing Add " ;
faultEx.Source = "AddUpdateTM"; <\/p>\n faultEx.Detail = eX.Message; <\/p>\n
throw new FaultException<CuboidFaultException>(faultEx); <\/p>\n
}<\/font><\/p>\n
Method AddTA (int nID, double dblL, double dblW, double dblH)<\/h5>\n
business logic for method AddTA<\/strong> is same as for AddTM.<\/strong> <\/p>\nMethod UpdateTM (int nID, double dblL, double dblW, double dblH)<\/h5>\n
UpdateTM<\/strong> is used to Update data to the table, passed cuboid information is updated to the CuboidInfo<\/strong> table, and its volume and surface area is calculated and updated to the CuboidDetail<\/strong> table. <\/p>\n[OperationBehavior(TransactionScopeRequired = true, TransactionAutoComplete = true)]
\n
public void UpdateTM(int nID, double dblL, double dblW, double dblH) <\/p>\n{<\/font><\/p>\n
Operations are decorated with <\/p>\n
TransactionScopeRequired = true<\/strong>,<\/font> that simply says that this operation requires a TransactionScope<\/strong>, if client does not propagate its transaction, transaction is created at the service level itself.<\/p>\nTransactionAutoComplete = true<\/font><\/strong> signifies, to complete the transaction scope automatically on successful execution of the operation; <\/p>\nif ((nID <= 0) || (dblL <= 0) || (dblW <= 0) || (dblH <= 0))
\n
{ <\/p>\n CuboidFaultException faultEx = new CuboidFaultException(); <\/p>\n
faultEx.Reason = "Any dimension of Cuboid (length\/width\/height) can not be zero or negative value"; <\/p>\n
faultEx.Source = "AddUpdateTM"; <\/p>\n
StringBuilder sbDetail = new StringBuilder(""); <\/p>\n
if (nID <= 0) sbDetail.Append("[ID is <= 0] "); <\/p>\n
if (dblL <= 0) sbDetail.Append("[Length is <= 0] "); <\/p>\n
if (dblW <= 0) sbDetail.Append("[Width is <= 0] "); <\/p>\n
if (dblW <= 0) sbDetail.Append("[Height is <= 0]"); <\/p>\n
faultEx.Detail = sbDetail.ToString(); <\/p>\n
throw new FaultException<CuboidFaultException>(faultEx); <\/p>\n
} <\/p>\n
<\/font>then method checks the passed parameters, in case they are zero or negative a FaultException<\/strong> is thrown. if the input parameters are permissible, then usual business logic proceeds, that includes.<\/p>\n
![\"TransactionBlock[5]\"](\"http:\/\/praveenkatiyar.wordpress.com\/wp-content\/uploads\/2013\/11\/transactionblock5.jpg\" "\\"TransactionBlock[5]\\"")
<\/a><\/p>\n