Wcf 从web.config读取连接字符串的步骤

IIS上的WCF服务。 我在从web.config文件读取连接字符串时遇到问题。 我的连接字符串如下所示：

    <connectionStrings>
  <add 
    name="ABC" 
    connectionString="DEF"
    providerName="GGG"
  />
</connectionStrings>

我在“cons_Webdata=……”中有错误消息：

对象引用未设置为对象的实例

怎么了？

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谢谢。

尝试使用ConfigurationManager而不是WebConfiguration Manager

protected void Application_Start(object sender, EventArgs e)
{                    
    cons_Webdata =  ConfigurationManager.ConnectionStrings["ABC"].ConnectionString;
}

否则，请使用示例代码

---

尝试使用ConfigurationManager而不是WebConfiguration Manager

protected void Application_Start(object sender, EventArgs e)
{                    
    cons_Webdata =  ConfigurationManager.ConnectionStrings["ABC"].ConnectionString;
}

否则，请使用示例代码

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查看如何在web应用程序中使用WebConfiguration Manager。您需要从配置文件中读取节连接字符串，然后使用它们，如下所示：

           // Get the connectionStrings section.
            ConnectionStringsSection connectionStringsSection =
                WebConfigurationManager.GetSection("connectionStrings")
                as ConnectionStringsSection;

            // Get the connectionStrings key,value pairs collection.
            ConnectionStringSettingsCollection connectionStrings =
                connectionStringsSection.ConnectionStrings;

            // Get the collection enumerator.
            IEnumerator connectionStringsEnum =
                connectionStrings.GetEnumerator();

            // Loop through the collection and 
            // display the connectionStrings key, value pairs.
            int i = 0;
            Console.WriteLine("[Display the connectionStrings]");
            while (connectionStringsEnum.MoveNext())
            {
                string name = connectionStrings[i].Name;
                Console.WriteLine("Name: {0} Value: {1}",
                name, connectionStrings[name]);
                i += 1;
            }

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查看如何在web应用程序中使用WebConfiguration Manager。您需要从配置文件中读取节连接字符串，然后使用它们，如下所示：

           // Get the connectionStrings section.
            ConnectionStringsSection connectionStringsSection =
                WebConfigurationManager.GetSection("connectionStrings")
                as ConnectionStringsSection;

            // Get the connectionStrings key,value pairs collection.
            ConnectionStringSettingsCollection connectionStrings =
                connectionStringsSection.ConnectionStrings;

            // Get the collection enumerator.
            IEnumerator connectionStringsEnum =
                connectionStrings.GetEnumerator();

            // Loop through the collection and 
            // display the connectionStrings key, value pairs.
            int i = 0;
            Console.WriteLine("[Display the connectionStrings]");
            while (connectionStringsEnum.MoveNext())
            {
                string name = connectionStrings[i].Name;
                Console.WriteLine("Name: {0} Value: {1}",
                name, connectionStrings[name]);
                i += 1;
            }

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