Hi, I am quite new to JS
I have a problem retrieving a value to an input field.

So, I have HTML:

<input type="text" name="conPrice" id="conPrice" size="16" maxlength="128" onKeyUp='price()'  />
<input type="text" name="OverP" id="OverP" size="16" readonly="readonly"/>
So, putting in a value in conPrice, I want a JavaScript to put a logic on sql statement:

PHP Code:
mysql_query("SELECT p_max, p_price, p_min  FROM dsd_price");
while (
$x_array mysql_fetch_array($x)){$max[] = $x_array['p_max']; $min[] = $x_array['p_min']; $price[] = $x_array['p_price'];}


<script type="text/javascript">
function price() {
 var frm=document.dsd_form;
 var a=frm.conPrice;
 var b=frm.OverP;
 var max = <?php echo json_encode($max); ?>;  
 var min = <?php echo json_encode($min);?>;
 var price = <?php echo json_encode($price);?>;

 for (counter=(min.length / 2); counter<(min.length + 1); counter++){
		if(a.value >= min[counter]){
			if(a.value <= max[counter]){
				b.value=min[counter]+ " " + max[counter] + " " + price[counter];
			else{b.value = 0;}
The trouble is, that I am not getting correct array part call