synapseindia php web development
TRANSCRIPT
Web Form FundamentalsWeb Form Fundamentals
OutlineOutline
Web FormsWeb Forms– Three sectionsThree sections
Order of ExecutionOrder of Execution
ViewstateViewstate
Web FormsWeb Forms
Three SectionsThree Sections1.1. Page DirectivesPage Directives
2.2. Code Declaration BlockCode Declaration Block
3.3. Code Render BlockCode Render Block
1. Page Directives1. Page Directives
Set page propertiesSet page properties– Language, debugging, tracing, …Language, debugging, tracing, …
Import additional class librariesImport additional class libraries– Common ones imported automaticallyCommon ones imported automatically
– Additional:Additional:Database access, data manipulation, web Database access, data manipulation, web services, drawing, communication…services, drawing, communication…
2. Code Declaration Blocks2. Code Declaration Blocks
Syntax:Syntax:<script runat=“server”><script runat=“server”>
//Server-side code here…//Server-side code here…
</script></script>
Locate:Locate:– Anywhere on page Anywhere on page usually at top usually at top– Another file Another file Code-Behind Code-Behind
3. Code Render Block3. Code Render Block
Contain:Contain:– HTMLHTML– TextText– Server ControlsServer Controls
Typically located below Code blockTypically located below Code block– Location does not affect outputLocation does not affect output
Code Render BlockCode Render Block
Can include ASP/PHP style tagsCan include ASP/PHP style tags– Syntax: <% =strLastName %>Syntax: <% =strLastName %>
Not used much in ASP.NETNot used much in ASP.NET
OutlineOutline
Web FormsWeb Forms– Three sectionsThree sections
Order of ExecutionOrder of Execution
ViewstateViewstate
Order of ExecutionOrder of Execution .NET is event driven.NET is event driven
– Events include:Events include: Page loadPage load Button clickButton click checkbox checkedcheckbox checked textbox text changedtextbox text changed etc.etc.
We write handlers (methods) to handle eventsWe write handlers (methods) to handle events Events fired in sequenceEvents fired in sequence Page Life CyclePage Life Cycle overview (for the curious) overview (for the curious)
Examples: Examples: – PostBack.aspxPostBack.aspx handout handout
OutlineOutline
Web FormsWeb Forms– Three sectionsThree sections
Order of ExecutionOrder of Execution
ViewstateViewstate
ViewStateViewState
Saves control dataSaves control data– Encoded in hidden form fieldEncoded in hidden form field
Benefit: convenienceBenefit: convenienceDisadvantageDisadvantage– Processing overheadProcessing overhead– BandwidthBandwidth– NovusHRNovusHR
Turn off with:Turn off with:– EnableViewState=“false”EnableViewState=“false”
Individual controlsIndividual controlsPage (in page directive)Page (in page directive)
SummarySummary
.NET Framework.NET Framework– Like a huge Lego setLike a huge Lego set
+5,000 types of pieces+5,000 types of pieces
– Mix and match pieces to build most anythingMix and match pieces to build most anything
Easily extendedEasily extended– Add new classesAdd new classes
Support for many languages & platformsSupport for many languages & platforms