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jamesclark clarkjamesclark clark 

how to write trigger to create Contact

Hi all,
I'm very new to Salesforce can any one help me to write atrigger to create a contact when a lead is created without converting the lead, with lead name and mobile and email and address.

Thank you in advance.
You don't need to write a trigger for this task, simply use Process Builder 

1. Create a Process Builder on Lead Object 
2. Select option only when record is created
3. For criteria select, Email is not null
4. Use Immediate action, Create a Record and select contact object and pass the value fro lead record 
UC InnovationUC Innovation
Give this a try:
trigger LeadTrigger on Lead (before insert) {
	List<Contact> contactList = new List<Contact>();
    for (Lead ld : Trigger.New) {
        Contact cont = new Contact();
        cont.FirstName = ld.FirstName;
        cont.LastName = ld.LastName;
        cont.MobilePHone = ld.MobilePhone;
        cont.Email = ld.Email;
        cont.MailingStreet = ld.Street;
        cont.MailingCity = ld.City;
        cont.MailingPostalCode = ld.PostalCode;
        cont.MailingState = ld.State;
        cont.MailingCountry = ld.Country;
    insert contactList;

Amit Chaudhary 8Amit Chaudhary 8
Hi jamesclark clark,

Code provide by UC Innovation will work for you. but if you want to learn how to write trigger please try trailhead.

Please check below post as well i hope that will help you

Trigger Best Practices | Sample Trigger Example | Implementing Trigger Framework
1) One Trigger Per Object

A single Apex Trigger is all you need for one particular object. If you develop multiple Triggers for a single object, you have no way of controlling the order of execution if those Triggers can run in the same contexts

2) Logic-less Triggers
If you write methods in your Triggers, those can’t be exposed for test purposes. You also can’t expose logic to be re-used anywhere else in your org.

3) Context-Specific Handler Methods
Create context-specific handler methods in Trigger handlers

4) Bulkify your Code
Bulkifying Apex code refers to the concept of making sure the code properly handles more than one record at a time.

5) Avoid SOQL Queries or DML statements inside FOR Loops
An individual Apex request gets a maximum of 100 SOQL queries before exceeding that governor limit. So if this trigger is invoked by a batch of more than 100 Account records, the governor limit will throw a runtime exception

6) Using Collections, Streamlining Queries, and Efficient For Loops
It is important to use Apex Collections to efficiently query data and store the data in memory. A combination of using collections and streamlining SOQL queries can substantially help writing efficient Apex code and avoid governor limits

7) Querying Large Data Sets
The total number of records that can be returned by SOQL queries in a request is 50,000. If returning a large set of queries causes you to exceed your heap limit, then a SOQL query for loop must be used instead. It can process multiple batches of records through the use of internal calls to query and queryMore

8) Use @future Appropriately
It is critical to write your Apex code to efficiently handle bulk or many records at a time. This is also true for asynchronous Apex methods (those annotated with the @future keyword). The differences between synchronous and asynchronous Apex can be found

9) Avoid Hardcoding IDs
When deploying Apex code between sandbox and production environments, or installing AppExchange packages, it is essential to avoid hardcoding IDs in the Apex code. By doing so, if the record IDs change between environments, the logic can dynamically identify the proper data to operate against and not fail
jamesclark clarkjamesclark clark
Hi Amit Chaudhary,
Thanks for ssharing the Information it helped me to know more about the trigger coding. And can you please give the sceniors which you have faced and sample triggers.
Best way to learn about apex trigger is 
Amit Chaudhary 8Amit Chaudhary 8
if you want to learn how to write trigger please try trailhead.