Show alert if the value in field exceeds character limit using workflow

Please find the following steps:

• Add an action “Show Message” in the workflow
• Select Before Field Edit in the “Trigger on” field
• Select the field in the “Triggering Client Fields”
• Add the formula in the Custom formula
  nlapiGetFieldValue(‘custrecord_item_req_display_name’).length >60
• Add alert message in the “Text” field