custom calculation script: display blank unless previous field is entered

[Disco Viking]

I have successfully added a custom calculation script to keep the fields blank until the necessary corresponding fields are filled, and then to remain blank if the calculation is <= zero. I would prefer the calculation fields to start blank, but once the calculations occur, display the total or zero if the result is <= zero. This way, if the recipient decides to print the form rather than fill it digitally, the lines won't display a zero, they will be blank for them to fill by hand. Example of my script:

event.value = this.getField("line5").value-this.getField("line6").value;
if(event.value <= 0)
    event.value = "";

[ls_rbls]

I am not sure if you're asking a question to a problem or actually stating a solution.

The script work fine on my end.

[Disco Viking]

I was able to find this script in another thread to accomplish this. However, I'm guessing there is a way to simplify this since the fields are only used for numbers.

(function () {

    // Get the input field values, as strings
    var sA = getField("line5").valueAsString;
    var sB = getField("line6").valueAsString;

    if (sA && sB) {  // If both of these input fields are not empty...

        // If both of these field values are zero when converted to a number...
        if (sA - sB <= 0) {
            event.value = 0;  // Set this field value to zero
            return;
        } else {
            event.value = sA - sB;  // Set this field value to this product
            return;
    }

    } else {
        // Blank this field since inputs are blank
        event.value = "";
        return;
    }

})()

[Disco Viking]

These // comments may be confusing since I modified the script

[Disco Viking]

This is probably more correct for just number fields? 

(function () {

    // Get the input field values
    var sA = getField("line5").value;
    var sB = getField("line6").value;

    if (sA && sB) {  // If both of these input fields are not empty...

        // If both of these field values are zero when calculated...
        if (sA - sB <= 0) {
            event.value = 0;  // Set this field value to zero
            return;
        } else {
            event.value = sA - sB;  // Set this field value to the result of this calculation
            return;
    }

    } else {
        // Blank this field since inputs are blank
        event.value = "";
        return;
    }

})()