how to validate field date range, despite allowable formats of m/d/yyyy and just yyyy.

Hi @Kristine372929303mo6 ,

In the following example, I utilize a validation script (as suggested by @try67 ) but emphasizing on using a regular expression for the input date rather than custom date formats. 

This script compares the year of the input date with both the current year and the year 2000. Additionally, I have restricted the input in the event target field to a maximum of 10 digits.

See example script below:

var f = event.value;
var inputDate = new RegExp("(^(1[0-2]|0[1-9])/(3[01]|[12][0-9]|0[1-9])/([0-9]{4})$|^[0-9]{4}$)");
var enteredDate = (new Date(f)).getFullYear();
var currentDate = (new Date()).getFullYear();
var initialDate = (new Date(2000, 01, 01)).getFullYear();

if (event.value !="") {

 if (event.value && inputDate.test(event.value) == true && (enteredDate >= initialDate && enteredDate <= currentDate)) {

   event.value = f 

   } else {

    app.alert("Please check for errors: \n\n*Enter Date Format as [ Month: \"03\", Day: \"14\", Year: \"2023\" ] or [ Year: 2019 ]\n\n\*Date cannot be older than year 2000\n\n\*Date cannot be greater than today's date");

   event.value = "";
    
  }
}    

You need to use a custom Validation script for this. Basically, it should be similar to your Format script where you figure out what pattern is used and convert it to a Date object. Then you need to convert that object to your two thresholds (today's date and 01/01/2000). If it's not between them, reject the value by setting event.rc to false.

To compare Date objects you can use the getTime method, which converts them to a number. You then compare those numbers to know if one date falls before or after the other.

@Kristine372929303mo6 maybe, I am doing something easier than that. I created a simple form. And made a PDF from it. I went into Acrobat, and click on 'Prepare Form' and hit 'Start'

I will double click on the first cell, so that it will open the 'Text Field Properties' - Go to 'Format' - Select 'Format' Category - Date - Select the date mm/dd/yyyy and then click on Close to apply

I will do it again in the cell right beside it. 

Click on Close, so that  can test this out...

Try that out?