在代码隐藏中动态设置ASP.NET自动完成扩展程序contextKey

我想在我的页面中使用ASP.NET自动完成。我使用我的内部对象来加载数据，应该使用作为实例页面字段值的参数来查询autocomplete。因为我不能在静态自动完成扩展程序方法中使用实例字段，所以我找到了一个可以用来实现我的目标的方法

我在asp.net页面中有文本框和自动完成扩展程序：

<asp:TextBox ID="PurchaseOrderItemsSearchTextBox" runat="server" EnableViewState="False"
                            SkinID="SalesReturnTextBox" AutoCompleteType="Disabled" 
                            AutoPostBack="True" OnTextChanged="PurchaseOrderItemsSearchTextBoxTextChanged" 
                            onload="PurchaseOrderItemsSearchTextBoxLoad" />
<ajax:AutoCompleteExtender runat="server" TargetControlID="PurchaseOrderItemsSearchTextBox" ID="OrderOrStockNumberExtender"
                            ServiceMethod="GetOrderOrStockNumbers" MinimumPrefixLength="2" CompletionInterval="1000" UseContextKey="True"/>

但当我运行页面并在静态web方法中设置断点（该方法应返回字符串数组）时，我发现contextKey为null

[WebMethod]
[ScriptMethod]
public static string[] GetOrderOrStockNumbers(string prefixText,int count, string contextKey)
{            
    string[] returnStrings = new string[] {"1","2"};
    return returnStrings;
}

非常感谢您的回答

---

鲁道夫。

我找到了解决办法。按属性值设置的ContextKey在ASP.NET中无法工作，因为我在文章中发现.NET 4.0在属性值中转义撇号

一种解决方案是在web配置中禁用编码属性值，但这可能会造成安全问题

<httpRuntime encoderType="HtmlAttributeEncodingNot"/>

---

现在contextKey由Javascript正确设置，我可以在GetOrderOrStockNumbers方法中使用它的值。

这些都不起作用，然后我发现您可以在页面加载下在代码中设置contextKey

ExtenderID.ContextKey = Control.SelectedValue;

而且它是有效的

protected void PurchaseOrderItemsSearchTextBoxPreRender(object sender, EventArgs e)
    {
        var textBox = sender as TextBox;
        if (textBox != null)
        {
            string sapCode = Customer.Company.SapCode;
            const string PURCHASE_ORGANIZATION = PURCHASE_ORGANIZATION_HP;
            string purchaseGroup = string.Empty;
            string firstDateTime = FirstDateTextBox.Text;
            var contextStrings = new[] {sapCode, PURCHASE_ORGANIZATION, purchaseGroup, firstDateTime};
            string context = string.Join(SEPARATOR, contextStrings);
            const string ON_KEY_UP = "onkeyup";
            const string ON_KEY_UP_VALUE = "SetOrderOrStockExtenderContextKey();";
            textBox.Attributes.Add(ON_KEY_UP, ON_KEY_UP_VALUE);

            //disable autocomplete in firefox
            DisableAutocompleteInFirefox(textBox);

            const string ORDER_OR_STOCK_NUMBER_SCRIPT_KEY = "OrderOrStockNumberScript";
            if (!ClientScript.IsClientScriptBlockRegistered(ORDER_OR_STOCK_NUMBER_SCRIPT_KEY))
            {
                Type type = GetType();
                var scriptTextBuilder = new StringBuilder();
                const string FUNCTION_NAME = "function SetOrderOrStockExtenderContextKey()";
                scriptTextBuilder.AppendLine(FUNCTION_NAME);
                const string LEFT_BRACKET = "{";
                scriptTextBuilder.AppendLine(LEFT_BRACKET);
                const string FIND_COMMAND = "$find(\'";
                scriptTextBuilder.Append(FIND_COMMAND);
                scriptTextBuilder.Append(OrderOrStockNumberExtender.ClientID);
                const string SET_COTEXT_KEY = "\').set_contextKey('";
                scriptTextBuilder.Append(SET_COTEXT_KEY);
                scriptTextBuilder.Append(context);
                const string END_OF_COMMAND = "');";
                scriptTextBuilder.AppendLine(END_OF_COMMAND);
                const string RIGHT_BRACKET = "}";
                scriptTextBuilder.AppendLine(RIGHT_BRACKET);

                string setContextKeyFunction = scriptTextBuilder.ToString();

                ClientScript.RegisterClientScriptBlock(type, ORDER_OR_STOCK_NUMBER_SCRIPT_KEY, setContextKeyFunction,
                                                       true);
            }
        }
    }

ExtenderID.ContextKey = Control.SelectedValue;