c# - 更改属性值

Question

我正在使用数据集，ConnectionString 存储在项目属性中。我试图编辑 ConnectionString 的值，但我收到消息说它是只读的！

我需要修改 ConnectionString，因为当我的应用程序部署到客户端时我必须更改它（需要更改用户和密码）。

那么如何修改 ConnectionString 呢？

Answer 1

Put it in your app.config (of course this could be improved or you could put the entire ConnectionString into the app.config like Karl Anderson mentioned) and don´t forget to Reference System.Configuration

<appSettings>
   <add key="dbServer" value="server"/>
   <add key="dbName" value="mydb"/>
   <add key="integratedSecurity" value="true"/>
   <add key="user" value=""/>
   <add key="pwd" value=""/>
</appSettings>

and in C#

public string GetConnectionString()
{
    var builder = new SqlConnectionStringBuilder();
    builder.DataSource = ConfigurationManager.AppSettings["dbServer"];
    builder.InitialCatalog = ConfigurationManager.AppSettings["dbName"];
    builder.IntegratedSecurtiy = Convert.ToBoolean(ConfigurationManager.AppSettings["integratedSecurity"]);

    string user = ConfigurationManager.AppSettings["user"];
    string pwd = ConfigurationManager.AppSettings["pwd"]
    if(!string.IsNullOrEmpty(user))
    {
       builder.UserId = user;
       builder.Password = YourCryptoProvider.Decrypt(pwd);
    }
    return builder.ToString()
}

Answer 2

Use the connectionStrings section of web.config, like this:

<connectionStrings>
    <add name="MyConnectionString" 
         connectionString="Data Source=YourComputer\sqlexpress;Initial 
         Catalog=YourDatabase;User ID=YourUserName;Password=YourPassword"
         providerName="System.Data.SqlClient" />
</connectionStrings>

Then you can read the value in your code, like this:

Configuration rootWebConfig = Configuration.WebConfigurationManager.OpenWebConfiguration("/MyWebSiteRoot");
ConnectionStringSettings connString;

// Are there any connection string values in web.config?
if (rootWebConfig.ConnectionStrings.ConnectionStrings.Count > 0)
{
    // Find the particular connection string we want by name
    connString = rootWebConfig.ConnectionStrings.ConnectionStrings["MyConnectionString"];

// Does the connection string exist in web.config?
if (connString != null)
{
    // Yes, so use it here
else
{
    // No, so generate error or alert user or whatever here
}