How to Calculate the Number of Days in a Month

Step 1: Create a Formula Field (Number)

Step 2: Paste this formula : DAY(DATE(YEAR(TODAY()),MONTH(TODAY())+1,1)-1)

Function :

Where MONTH(TODAY()) is the month for which you want to return the number of days, and YEAR(TODAY()) is the year. This function calculates the first day of the next month and subtracts 1, which equals the last day of the current month. The DAY function then gives you the day of the month.

http://community.salesforce.com/sforce/board/message?board.id=apex&message.id=18418#M18418

http://community.salesforce.com/sforce/board/message?board.id=custom_formula&message.id=5548&jump=true#M5548

Displaying Running Digital Clock

Scenario..

The technical support / customer service will raise a case on behalf the account user and follow up the case,
Whenver the technical support try to reach the case contact he/she want to know the current time of case contact.


So i have decided to display the running digital clock in case detail page:

some thing like this...

sceern shot of case detail page :



Step 1: Create a Picklist field in contact called TimeZone__c with field values like ...

(GMT+05:30) India Standard Time (Asia/Calcutta)

(GMT-05:00) Eastern Daylight Time (America/New_York)

(GMT-11:00) Samoa Standard Time (Pacific/Pago_Pago)

Step 2: upload the clock images in static resources.

Step 3: Create a visualforce page

Apex Page :
<apex:page standardController="case" tabStyle="case" extensions="contact_clock">

<apex:form >

<table bgcolor="#c9c299">
<th><apex:image value="{!$Resource.hand}"/></th>
<th><apex:outputText value="Your Time " /></th>
<th width="5"></th>
<th>
<apex:image id="Uh1" value="{!h1}"/>
<apex:image id="Uh2" value="{!h2}"/>
<apex:image id="Um" value="{!$Resource.dgc}" />
<apex:image id="Um1" value="{!m1}"/>
<apex:image id="Um2" value="{!m2}"/>
<apex:image id="Us" value="{!$Resource.dgc}"/>
<apex:image id="Us1" value="{!s1}"/>
<apex:image id="Us2" value="{!s2}"/>
<apex:image id="Uampm" value="{!ampm}" />
<apex:actionPoller action="{!UserTime}"
rerender="Uh1,Uh2,Us1,Us2,Um1,Um2,Uampm,r1" interval="5" />
</th><th width="120"  ><apex:outputText value="{!a}" id="r1"  /></th>
<th><apex:image value="{!$Resource.hand}"/></th>
<th><apex:outputText value="Contact Time " /></th>
<th width="5"></th>
<th>
<apex:image id="Ch1" value="{!h1}"/>
<apex:image id="Ch2" value="{!h2}"/>
<apex:image id="Cm" value="{!$Resource.dgc}"/>
<apex:image id="Cm1" value="{!m1}"/>
<apex:image id="Cm2" value="{!m2}"/>
<apex:image id="Cs" value="{!$Resource.dgc}"/>
<apex:image id="Cs1" value="{!s1}"/>
<apex:image id="Cs2" value="{!s2}"/>
<apex:image id="Campm" value="{!ampm}" />
<apex:actionPoller action="{!ContactTime}"
rerender="Ch1,Ch2,Cs1,Cs2,Cm1,Cm2,Campm,Cr1" interval="5" />
</th><th width="120"  ><apex:outputText value="{!a}" id="Cr1"  /></th>
</table>
</apex:form>
</apex:page> 

Apex Class:

public with sharing class contact_clock {
public contact_clock(ApexPages.StandardController controller) { }
String idr = System.currentPageReference().getParameters().get('id');
string urlr = 'https://na5.salesforce.com/resource/1246944823000/dg';
DateTime tall;    Boolean flag;    String temp,tempw,temph,tempm,sDate,ap,s1,s2,m1,m2,h1,h2,dt;
Public PageReference UserTime() {
flag = false;  geta(); return null;
}
Public PageReference ContactTime() {
flag = true;  geta(); return null;
}
public string geta() {
tall = Datetime.now();
if(flag == true){
contact con2 = [select TimeZone__c from contact where id in (select contactid from case where id=:idr)];
tempw = con2.TimeZone__c.substring(4,5);
if(tempw == '+'){temph = con2.TimeZone__c.substring(5,7);}else{
  temph = con2.TimeZone__c.substring(4,7);
}
integer addh = integer.valueof(temph);
tempm =  con2.TimeZone__c.substring(8,10); 
integer addm = integer.valueof(tempm); 
datetime newDateh = tall.addHours(addh); 
datetime  newDatem = newDateh.addminutes(addm); 
sDate = newDatem.formatgmt('hh:mm:ss a MM-dd-yyyy');}else{
sDate = tall.format('hh:mm:ss a MM-dd-yyyy');}
s2 = sDate.substring(7,8);
s1 = sDate.substring(6,7);
m2 = sDate.substring(4,5);
m1 = sDate.substring(3,4);
h2 = sDate.substring(1,2);
h1 = sDate.substring(0,1);
ap = sDate.substring(9,11);
dt = sDate.substring(11);
return dt;
}   
public string gets1() {  
return urlr+s1;  
}   
public string gets2() { 
return urlr+s2;  
}  
public string getm1() { 
return urlr+m1;  
} 
public string getm2() { 
return urlr+m2;  
} 
public string geth1() { 
return urlr+h1;  
}  
public string geth2() {  
return urlr+h2; 
} 
public string getampm() { 
return urlr+ap;
}   
}