创建一个触发器来验证 Product 对象的数据

Question

I have an apex trigger (before insert/update) and a helper class to that trigger. The problem is: When creating an object record, the trigger should check if the AddedDate field is filled and if it's not - then assign it today's date and current time.

And when I create and update a Product object record, the trigger must check the length of the Description field, if the field is longer than 200 characters, I must trim it to 197 characters and add a triple to the end of the line. What am I doing wrong and how should I proceed?

:

trigger ProductTrigger on Product__c (before insert, before update) { 
       if(Trigger.isUpdate && Trigger.isAfter){
        ProductTriggerHelper.producthandler(Trigger.new);
    }


}

:

public class ProductTriggerHelper {

    public static void producthandler(List<Product__c> products) {
        Schema.DescribeFieldResult F = Product__c.Description__c.getDescribe(); 
        Integer lengthOfField = F.getLength();

        //List<Product__c> prList = new list<Product__c>(); 
        for(Product__c pr: products){

            pr.AddedDate__c=system.today();

            if (String.isNotEmpty(pr.Description__c)) {
               pr.Description__c = pr.Description__c.abbreviate(lengthOfField);
            }
        } 
    }

}

Answer 1

According to your requirements

When creating an object record, the trigger should check if the AddedDate field is filled and if it's not - then assign it today's date and current time.

You aren't doing that.

Change pr.AddedDate__c=system.today(); to

if (pr.AddedDate__c == null) { pr.AddedDate__c=system.today(); }

Also according to the abbreviate function documentation the parameter it takes is the max length including the 3 elipses.

So change pr.Description__c = pr.Description__c.abbreviate(lengthOfField); to

pr.Description__c = pr.Description__c.abbreviate(200);

Answer 2

To add to Programmatic 's answer...

You defined the trigger as before insert, before update . Cool, that's perfect place for doing data validations, field prepopulation... And you'll get save to database for free!

But then this clashes with next line if(Trigger.isUpdate && Trigger.isAfter){ . With this setup it'll never fire. Either remove the if completely or (if you think trigger can get more events in future) go with trigger.isBefore && (trigger.isInsert || trigger.isUpdate) .

PS It's datetime field? So pr.AddedDate__c=system.now(); is better