asp.net core docker Events in JavaScript

Link for all dot net and sql server video tutorial playlists
http://www.youtube.com/user/kudvenkat...

Link for slides, code samples and text version of the video
http://csharp-video-tutorials.blogspo...

What is an event
An event is a signal from the browser that something has happened. For example,
1. When a user clicks on an HTML element, click event occurs
2. When a user moves the mouse over an HTML element, mouseover event occurs

When events occur, we can execute JavaScript code or functions in response to those events. To do this we need to associate JavaScript code or functions to the events. The function that executes in response to an event is called event handler.

In JavaScript, there are several ways to associate an event handler to the event
1. Using the attributes of an HTML tag
2. Using DOM object property
3. Using special methods

In this video we will discuss associating event handler methods to events using the attributes of HTML tags.

In the following example, the code to execute in response to onmouseover & onmouseout events is set directly in the HTML markup. The keyword "this" references the current element. In this example "this" references the button control.

[input type="button" value="Click me" id="btn"
onmouseover="this.style.background= 'red'; this.style.color = 'yellow'"
onmouseout="this.style.background= 'black'; this.style.color = 'white'" /]

The above example, can be rewritten as shown below. In this case the code to execute in response to the event is placed inside a function and then the function is associated with the event.

[input type="button" value="Click me" id="btn"
onmouseover="changeColorOnMouseOver()"
onmouseout="changeColorOnMouseOut()" /]

[script type="text/javascript"] function changeColorOnMouseOver() { var control = document.getElementById("btn"); control.style.background = 'red'; control.style.color = 'yellow'; } function changeColorOnMouseOut() { var control = document.getElementById("btn"); control.style.background = 'black'; control.style.color = 'white'; }
[/script]

Events are very useful in real-world applications. For example they can be used to
1. Display confirmation dialog box on submitting a form
2. Form data validation and many more

How to show confirmation dialog in JavaScript

[input type="submit" value="Submit" id="btn" onclick="return confirmSubmit()" /]
[script type="text/javascript"] function confirmSubmit() { if (confirm("Are you sure you want to submit")) { alert("You selected OK"); return true; } else { return false; confirm("You selected cancel"); } }
[/script]

JavaScript form validation example : In this example, both First Name and Last Name fields are required fields. When you type the first character in any of the textbox, the background colour is automatically changed to green. If you delete all the characters you typed or if you leave the textbox without entering any characters the background colour changes to red indicating the field is required. We made this possible using onkeyup and onblur events.

onkeyup occurs when the user releases a key.
onblur occurs when an element loses focus.

[table] [tr] [td] First Name [/td] [td] [input type="text" id="txtFirstName" onkeyup="validateRequiredField('txtFirstName')" onblur="validateRequiredField('txtFirstName')"/] [/td] [/tr] [tr] [td] Last Name [/td] [td] [input type="text" id="txtLastName" onkeyup="validateRequiredField('txtLastName')" onblur="validateRequiredField('txtLastName')"/] [/td] [/tr]
[/table]
[script type="text/javascript"] function validateRequiredField(controlId) { var control = document.getElementById(controlId); control.style.color = 'white'; if (control.value == "") { control.style.background = 'red'; } else { control.style.background = 'green'; } }
[/script]

asp.net core docker Events in JavaScript
335 Likes	335 Dislikes
76,831 views views	524K followers
Education	Upload TimePublished on 11 Jan 2015

Related keywords

wcf vs web api,ado.net core,sql server management studio,webkinz,javascript tutorial for beginners ppt,webadvisor,craigslist nj,wcf one piece,asp.net core 3,ajax players,weber grill parts,webtoon,tutorials by hugo,csharp corner,mvc design pattern,asp.net machine account,servers for minecraft,asp.net core dependency injection,ado.net tutorial,services angular,ajax ontario,asp.net mvc tutorial,asp.net cos'è,csharp assembly,tutorialspoint python,sql join,services briefcase,asp.net core web api,ajax jquery,wccftech,craigslist ny,asp.net zero,csharp foreach,server memes,sql date format,services online,javascript tutorial for beginners to advanced,chase,serverless architecture,server resume,wcf c#,server books,tutorialspoint javascript,mvcc connect,ado.net mysql,services technologies gps,ajax deadpool,server jobs,cvs,website,mvc tutorial,costco hours,wcf service application,javascript tutorial for beginners 2019,tutorialspoint spring,serverless,wcf soap,wcf cat,cool math games,wcf test client,services & training hse colombia sas,servicestack,citibank,asp.net core identity,sql union,ajax parking,sql database,asp.net core logging,mvconnect,cunyfirst,asp.net guida,wcf nba,csharp download,wcfi foundation,javascript tutorial for beginners pdf,csharp online,wcf authentication,javascript tutorial for beginners javatpoint,tutorials near me,http://asp.net,server 2019,chernobyl,ado.net descargar,javascript tutorial for beginners pdf free download,web of dreams,serverminer,ajax cleaner,ado.net visual studio 2019,javascript tutorial for beginners with examples in hindi,webassign,ado.net vs entity framework,ado.net visual studio 2017,csharp list,sql like,asp.net mvc,asp.net core tutorial,sqlite,wcfm,ajax roster,mvc architecture,http://ado.net,asp.net core mvc,ajax soccer,server hosting,javascript tutorial for beginners in urdu,wcfi,ajax dish soap,capital one,javascript tutorial for beginners in tamil,server rack,tutorialspoint html,csharp interface,craigslist,webroot,tutorialspoint reactjs,ajax request,wcf dragon ball,asp.net core 2.2,tutorialspoint python 3,sql developer,webster,services transmission company sas,sql group by,asp.net core signalr,services manager,mvc framework,ajax paving,mvc near me,javascript tutorial for beginners mosh,tutorialspoint spring boot,mvc map,csharp online compiler,asp.net download,sql between,ado.net c# pdf,services tag dell,wcf 2019 nba,csharp switch,ado.net ventajas y desventajas,csharpstar,wcf tutorial,tutorialspoint,ajax meaning,csharp-video-tutorials.blogspot,tutorials dojo,central park 5,javascript tutorial for beginners udemy,csharp string format,ado.net c#,asp.net core github,server status,ajax fc,server jobs nyc,asp.net core swagger,sql formatter,credit karma,services group,server error in '/' application,services windows,asp.net core 3.0,sql injection,tutorialspoint c#,wcf ria services,calculator,ado.net entity data model,sql insert,tutorialspoint tableau,services google play apk,sqlyog,asp.net core 3 release date,sql server,server job description,tutorials by a,servicenow,webcam,mvc hours,webmd symptom,csharp array,javascript tutorial for beginners ej media,csharp enum,ajax call,asp.net core 2. guida completa per lo sviluppatore,asp.net core,server pro,server status ffxiv,cheap flights,webcrims,asp.net core hosting,services sas,tutorialspoint java,tutorialspoint java compiler,webmd,csharp to json,college football,ado.net dataset,csharp dictionary,cnn,website builder,tutorialspoint sql,asp.net web api,server side rendering,javascript tutorial for beginners youtube,weber grills,sql server 2017,tutorialspoint spark,mvc nj,ado.net oracle,asp.net core download,javascript tutorial for beginners telusko,csharp to vb.net,javascript tutorial for beginners in hindi,webster bank,webstaurant,tutorialsystems,ajax post,services fms publish announcement,services.msc no abre,ajax jersey,csharp operator,asp.net core razor pages,server duties,asp.net core environment variables,csharp random,century 21,javascript tutorial for beginners w3schools,services consultores,services consulting,mvcsd,services.msc,mvcsc,ado.net pdf,asp.net core configuration,ajax marvel,sql update,asp.net tutorial,mvc medical,ado.net entity data model visual studio 2019,wcfs international curriculum,mvc2,javascript tutorial for beginners step by step pdf,ado.net entity data model visual studio 2017,chase online,wcf api,costco,server jobs near me,webex,sql meaning,sql tutorial,sql commands,ado.net entity framework,ajax tavern,javascript tutorial for beginners edureka,tutorialsteacher,ajax javascript,services desk,javascript tutorial for beginners step by step,ajax greek,csharp tutorial,mvc pattern,ado.net sql server,ado.net connection,asp.net identity,mvcu,asp.net core middleware,javascript tutorial for beginners free,wcf web service,mvc webadvisor,web store,mvcc,webmail,mvci,mvctc,