Show Alert and prevent Save when Duplicate Customer record is created

With Duplicate Detection Feature the users are notified of potential duplicates upon record creation.
When creating a new record and entering matching data in fields that are set up as duplicate criteria, a warning is shown at the top of the page with a link to the potential duplicates.
Although NetSuite can detect these duplicates, it does not prevent a new record from being saved.

Use case:
Prevent Duplicate Customer record creation by showing a popup message.

Solution:
Create a User Event Script with Save Record Function that would check if there are any records already existing with these details and show a popup message to prevent from saving.

1. Script code example:

   function detectDuplicate_OnSave(){var fldMap = new Array();var email = nlapiGetFieldValue('email');fldMap['email'] = email; var duplicateRecords = nlapiSearchDuplicate( 'customer', fldMap ); 	if (duplicateRecords != null) 	{		alert('Record cannot be saved, duplicate detected');		return false;    }else 	return true;}

2. Create the Client Script record in NetSuite through Customization > Scripting > Scripts > New > Client Script.
   - Scripts tab: select the Script File = the name of the script you have uploaded in step 1 and in Save Record Function = detectDuplicate_OnSave
   - Deployments tab: Applies To = Csutomer, Status = Released, Select Audience

For more information about Client Scripts please visit SuiteAnswers Article 19194 Running Scripts in NetSuite Overview .

DISCLAIMER: The sample code described herein is provided on an "as is" basis, without warranty of any kind, to the fullest extent permitted by law. Oracle + NetSuite Inc. does not warrant or guarantee the individual success developers may have in implementing the sample code on their development platforms or in using their own Web server configurations.

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