[рони]

dasha862,

<input type="text" id="txtCommand">
<script>
	var blackList = ['поле'];
 	document.getElementById("txtCommand").addEventListener('input', function() {
	var expr = new RegExp(blackList.join('|'), 'ig');
	if (expr.test(this.value)) {
    expr.lastIndex = 0;
	this.value = this.value.replace(expr, '');
	}
}, false)
</script>