Event Handlers

• ON CLICK EVENT HANDLER:
Click


• Coding "href=JavaScript:void(0)" prevents the entire page from being reloaded which is what would happen if href="#"
SAMPLE CODE <a href="JavaScript:void(0)" onClick="alert('Hi');" >Click</a>
• EXECUTING MULTIPLE STATEMENTS WITH A ON CLICK EVENT HANDLER:
Click

• Buttons:


SAMPLE CODE <input type="button" value="click" onClick="alert('Hello world!');">
• On focus and On Blur TO CHANGE COLORS OF A TEXT BOX

Email:


SAMPLE CODE <input type="text" size="30" onFocus="this.style.backgroundColor='yellow';" onBlur="this.style.backgroundColor='white';">
• onSubmit - VALIDATE THAT THE EMAIL BOX HAS A VALUE ENTERED


email:


SAMPLE CODE <form onSubmit="checkAddress('idemail');"> email: <input type="text" id="idemail"> <input type="submit" value = "Submit"> </form> <SCRIPT type="text/javascript" > function checkAddress(fieldId) { alert("fieldId is: " + fieldId); if (document.getElementById(fieldId).value == "") { alert("Email address required."); } } </Script>