E

early binding (COM), 1155

#elif preprocessor directive, 71–72

#else preprocessor directive, 71–72

EnableVisualStyles method (Application class), 785–786

#endif preprocessor directive, 71–72

EndOfStreamException class, 329

EndReceive() method (MessageQueue class), 1111

#endregion preprocessor directive, 72–73

Enterprise Services

automatic transactions, 1068, 1078

business service layer for, 1067

client application, 1077–1078

Component Services explorer for, 1075–1077

contexts and, 1067–1068

current issues, 1126

data service layer for, 1067

defined, 1065

deployment, 1073–1075

distributed transactions, 1068

history of, 1066

installer packages for, 1074–1075

loosely coupled events, 1069

Microsoft Application Center Server and, 1067

object pooling, 1068

overview, 1065–1069

presentation service layer for, 1067

queued components, 1069

role-based security, 1068

sample application, 1080–1090

ServiceConfig class, 1090–1091

ServiceDomain class, 1090, 1091

services without components, 1069, 1090–1093

simple COM+ application, 1070–1073

transactions, 1068, 1078–1080

WCF and, 1146–1147

enumerations (enums)

benefits of using, 56

collection enumerators, 246–247

converting from a string, 57

defining, 55, 56

described, 55

EnumFontFamilies example, 878–880

FileStream class, 1208

instantiated as structs, 57

for messages in message queues, 1109–1110

retrieving string representations, 57

retrieving values, 57

TimeOfDay example, 56

enumerators for collections, 248

EnumFontFamilies example, 878–880

Equals() method

comparing reference types for equality, 146–147

comparing value types for equality, 147, 148

described, 107

overriding for comparisons, 146–147, 148

overriding for dictionaries, 264, 266, 267

static version, 147

virtual version, 146–147

equals sign (=)

as assignment operator, 34, 134–135

as comparison operator (==), 48, 134–135, 147

error handling. See also exceptions

catch blocks, defined, 330

catching exceptions from other code, 336–337

catching exceptions from predefined classes, 330–340

catching user-defined exceptions, 341–343

choosing exception type to throw, 334–335

for code access permissions, 472

COM, 1158

defining your own exception classes, 346–348

exceptions for, 16–17

exceptions not handled and, 338

finally blocks, defined, 330

handling different exceptions in different places, 340

modifying the type of exception, 340

multiple catch blocks for, 331, 332–336

nested throw statements for, 332

nested try blocks for, 338–340

for overflow and array out-of-bounds, 331–332

process for, 330

for releasing database resources, 586, 587–588

SimpleExceptions class, 333–336

syntax, 330–331

SystemException properties for, 337

throwing an exception, defined, 331

throwing user-defined exceptions, 343–346

for thrown SecurityException, 480, 482, 492

try blocks, defined, 330

for Windows Forms controls, 767–769

#error preprocessor directive, 72

ErrorProvider component (Windows Forms)

clearing, 768

overview, 767–768

using one error provider per form, 768–769

escape sequences

for regular expressions, 236, 238–240

searching for escape meta-characters, 240

table summarizing, 44, 239

EvaluateException, 807

event logging for services

adding for other application types, 1305–1306

adding for service classes derived from

ServiceBase, 1302, 1305

adding to QuoteServer, 1306–1307

architecture, 1304

AutoLog property of ServiceBase class for, 1302, 1305

classes, 1305

creating an event log listener, 1307–1308

custom event logging, 1303

example log entry, 1302–1303

trace messages and, 1307

event sink library (.NET Remoting), 1059–1060

EventArgs class, 188–189, 832

event-booking application

AddEvent() method, 995

adding events to the database, 931–933

ADO.NET and data binding for, 926–933

Application_Start() event handler, 994

attendeeList control, 928

Attendees table, 926–927

binding to controls on the Web page, 999

binding to the database, 927–928

calendar_DayRender() event handler, 930–931

calendar_SelectionChanged() event

handler, 930

client for Web service extension, 997–1001

code-behind file, 929–930

creating the Web site, 920–921, 926

customizing the calendar control, 928–931

data binding for client application, 1000

data display with templates, 935–939

database for, 926–927

DataList control, 937–938

DataSet objects with Web services, 997

declaring objects needed for database access, 995–996

deleting data sources for client application, 998

event list display, 933–935

EventList control, 936–937

EventList_SelectedChanged() method, 1001

Events table, 927

ExecuteNonQuery() method, 932–933

extracting event data, 930

form for, 920–923

FormView control, 936, 937–938

GetData() method, 994–995

GetFreeDate() method, 929–930, 933

GridView control, 933–934

Label control, 920

Lock() and Unlock() methods, 996

MRBEventData control, 929

MRBService service, 994–995

Page_Load() event handler, 924

queryResult with, 996–997

resultLabel control, 924

results of a submission, 924–925

roomList control, 928

Rooms table, 927

SqlDataSource controls, 927–928

storing the DataSet for client application, 998–999

submitButton_Click() event handler, 924, 931–932, 934, 1000–1001

using statements, 995

ValidationSummary control, 921

Web server controls for, 921–924

Web service for, 993–997

web.config file, 993

EventHandler delegate, 186–188

EventHandler<TEventArgs> generic delegate, 302–303

EventList control, 936–937

EventLog component, 1307–1308

events

Click event example, 186–188

COM event handling, 1158, 1166–1168, 1181–1182

as data members of classes, 85

defining, 188

delegates for, 185

described, 85

focus, gaining and losing for controls, 761

generating, 188–192

keyboard events, 760–761

messages wrapped in, 185

methods for handling, 186–188

mouse events, 760

names of event handlers, 187

.NET Remoting and, 1056–1062

receiver's view of, 185–188

senders for, 185–186, 188

threading workaround using, 350

user control event handler, 797–798

for user controls (ASP.NET), 948

for Windows Form user interaction, 760–761

Windows Services event logging, 1302–1308

exceptions. See also error handling

for aborting threads, 354

base class exception classes, 328–330

catching from predefined classes, 330–340

catching user-defined exceptions, 341–343

choosing type to throw, 334–335

class hierarchy, 329–330

debugging and, 406–407

handling different exceptions in different places, 340

modifying the type of, 340

multiple catch blocks for, 331, 332–336

nested throw statements for, 332

in .NET, 16–17

not handled, outcome of, 338

SimpleExceptions class, 333–336

throwing, defined, 331

throwing from catch and finally blocks, 339

throwing user-defined exceptions, 343–346

user-defined exception classes, 340–348

ExecuteNonQuery() method, 591, 932–933

ExecuteReader() method, 591–592

ExecuteScalar() method, 592–593

ExecuteXmlReader() method, 593–594

Exists() method (MessageQueue class), 1104–1105

explicit type conversions, 142–145, 158. See also

user-defined casts

exposing Web services, 987–990

extern modifier, 125

extracting characters from strings, 224