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HTML

<input type="email" id="reg_email"></input>
<input type="email"id="reg_email2"></input>
<div class="field_confirm"></div>
<div class="field_confirm"></div>
<div class="field_confirm"></div>
<div class="field_confirm"></div>

JavaScript

function GOPRO_pfFieldConfirmation(oField1, oField2, oMarkerField, bCaseSens) {
    var $field1 = $(oField1), $field2 = $(oField2);

    $(oField1).focus(function() {
        //put these in the focus event, so they are bound everytime.
        var GOPRO_iFieldLen1 = $field1.val().length;
        var GOPRO_iFieldLen2 = $field2.val().length;
        var GOPRO_sFieldVal1 = $field1.val();
        var GOPRO_sFieldVal2 = $field2.val();
        var GOPRO_sFieldSub = GOPRO_sFieldVal1.substring(0, GOPRO_iFieldLen2);
        //if not case sensitive, make all upper case  
        if (bCaseSens == false) {
            GOPRO_sFieldVal1 = GOPRO_sFieldVal1.toUpperCase();
            GOPRO_sFieldVal2 = GOPRO_sFieldVal2.toUpperCase();
            GOPRO_sFieldSub = GOPRO_sFieldSub.toUpperCase();
        }

        console.log(GOPRO_iFieldLen1);
        if ((GOPRO_sFieldVal1 == GOPRO_sFieldVal2) && GOPRO_iFieldLen1 > 0) {
            //GreenMarker();
        } else if (GOPRO_iFieldLen1 > 0 && GOPRO_iFieldLen2 > 0) {
            //RedMarker();
        } else {
            //NoMarker();
        }
    });
}

GOPRO_pfFieldConfirmation('#reg_email', '#reg_email2', '.field_confirm:eq(3)', false);