trigger emailquotetrig on Opportunity (after insert, after update) {
	List<quote> quotelist=new List<quote>();
	for(opportunity opp:trigger.new){
		quote q=new quote();
		if(opp.StageName=='Closed Won'){
			try{
			q=[select primary__c,name,id,opportunityid from quote where primary__c=true and opportunityid=:opp.id];
			//string strurl='https://ap1.salesforce.com/q.id';
	Messaging.reserveSingleEmailCapacity(1);
	// Now create a new single email message object 
	Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
	// Strings to hold the email addresses to which you are sending the email
	String[] toAddresses=new String[]{'patlammagari@gmail.com'};
	// Assign the addresses for the To  lists to the mail object.  
	mail.setToAddresses(toAddresses);
	// Specify the address used when the recipients reply to the email.
	mail.setReplyTo('ramanareddy477@gmail.com');
	// Specify the name used as the display name.
	mail.setSenderDisplayName('Salesforce Support');
	// Specify the subject line for your email address.
	mail.setSubject('Please click on the link to view the quote record');
	// Set to True if you want to BCC yourself on the email.  
	mail.setBccSender(false);
	// Optionally append the salesforce.com email signature to the email.  
    // The email address of the user executing the Apex Code will be used.
	mail.setUseSignature(false);
	// Specify the text content of the email. 
	mail.setPlainTextBody('https://ap1.salesforce.com/'+ q.id);
	// Send the email you have created. 
	Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail });
			}catch(system.QueryException e){
				opp.adderror('Need to select a primary quote among the related quotes'); 
			
			}
			
		}

	}
}
      Thanks in advance.
--Regards,
forceapp.