private IEntityFrameworkDataServicesProvider GetDataServicesProvider(ShellSettings shellSettings)
{
var providerName = shellSettings.GetDataProvider();
if (string.IsNullOrWhiteSpace(providerName))
throw new ArgumentException("因为数据服务提供名称为空，所以无法确定数据服务提供者。");
var provider = _dataServicesProviders.FirstOrDefault(
p => string.Equals(p.ProviderName, providerName, StringComparison.OrdinalIgnoreCase));
if (provider == null)
throw new NotSupportedException(string.Format("找不到名称为：{0}的数据服务提供程序。", providerName));
return provider;
}
