var formblock;
var forminputs;
 
function prepare() {
  formblock= document.getElementById('form_inbox');
  forminputs = formblock.getElementsByTagName('input');
}

function select_all(name, value) {
  for (i = 0; i < forminputs.length; i++) {
    // regex here to check name attribute
    var regex = new RegExp(name, "i");
    if (regex.test(forminputs[i].getAttribute('name'))) {
      if (value == '1') {
        forminputs[i].checked = true;
      } else {
        forminputs[i].checked = false;
  }
    }
  }
}

if (window.addEventListener) {
  window.addEventListener("load", prepare, false);
} else if (window.attachEvent) {
  window.attachEvent("onload", prepare)
} else if (document.getElementById) {
  window.onload = prepare;
}