javascript - javascriptでSQL関数を書く方法は？

Question

メソッドを使用してfunction、ユーザーの入力により、データベースでアイテムの価格を自動的に取得したいと考えています。textbox("@Html.TextBox("ItemID")")handle

//SalesSub.cs
public class SalesSub
{
    public string ItemID { get; set; }
    public int Qty { get; set; }
    public decimal UnitPrice { get; set; }
}

//Create.cshtml
<script type="text/javascript">
function handle(e) {
     //Detect when the user press 'Enter' Or 'Tab' Key
     var keyCode = e.keyCode || e.which;
     if (keyCode === 13 || keyCode == 9) {
         var itemID = $('#ItemID').val()
         //Get the item ID in the textbox value, 
         //so how to search the price of the 
         //item in database? Using SQL or Others?
         $('#UnitPrice').val() = //Result After Search
     }
     return false;
 }

@using (Html.BeginForm()) {
@Html.ValidationSummary(true)
</script>
<label>Item ID :</label>
 **@Html.TextBox("ItemID", string.Empty, new { onkeydown = "handle(event)" })**
<label>Qty :</label>
    @Html.TextBox("Qty")
<label>Sales Price :</label>
    @Html.TextBox("UnitPrice")
}