Trigger Examples:
What is Trigger? Trigger is piece of code that is executes before and after a record is Inserted/Updated/Deleted from the force.com database.
Trigger Events: Before Insert, Before Update, Before Delete, After Insert, After Update, After Delete and after undelete.
Example 1:
trigger trigEventsTest on Department__c (before insert,after insert,before update,after update) {
if(Trigger.isInsert) {
system.debug('***IsINSERT*****');
}
if(Trigger.isUpdate) {
system.debug('******IsUpdate*****');
}
if(Trigger.isBefore && Trigger.isInsert) {
system.debug('****IsBefore and IsInsert*****');
}
if(Trigger.isAfter && Trigger.isInsert) {
system.debug('*******IsAfter and IsInsert*****');
}
if(Trigger.isBefore && Trigger.isUpdate) {
system.debug('*****Before Update******');
}
}
Example 2:
Account with Multiple Contacts:
trigger Con5Insert on Account (after insert) {
if(Trigger.isAfter) {
system.debug('****New Account Record is ******'+Trigger.new);
Contact objContact ;
List<Contact> lstcon = new List<Contact>();
for(Integer i=1;i<=5;i++) {
objContact = new Contact(lastname='AAAAAAAAA'+string.valueof(i),AccountId=Trigger.new[0].Id);
lstcon.add(objContact);
}
system.debug('****List Of Contacts *****'+lstcon.size());
insert lstCon;
}
}
Example 3:
Trigger.new and Trigger.old
trigger trigEventsTest on Department__c (before update,after update) {
if (Trigger.new[0].name != Trigger.new[0].name) {
system.debug('*****Value Changed******');
} else {
system.debug('*****Value did not change******');
}
}
Example 4:
Add Error:
trigger trigEventsTest on Department__c (before insert) {
if(Trigger.new[0].name=='India') {
Trigger.new[0].name.addError('Name should not be India');
}
}
in 3rd example if condition may be wrong……………..
plz check it…