问题描述
我有一个使用SQL Server空间数据类型的.net4.5 Web应用程序项目.
I have a .net4.5 web application project that uses SQL server spatial datatype.
在开发机器上可以在本地完美地工作，但是当尝试在具有空间数据的表上运行查询时，当我收到以下错误消息:
Works perfectly locally on development machine, but when deployed to application server I get the following error when trying to run queries on table with spatial data:
System.InvalidOperationException: DataReader.GetFieldType(5) returned null.
我发现，如果服务器上未安装SQLServer，则不支持空间数据类型.
I found out that if SQLServer is not installed on the server, there is no support for spatial data types.
因此，我将nuget软件包安装到了我的项目中:
Therefore I installed the nuget package to my project:
Install-Package Microsoft.SqlServer.Types
这添加了对Microsoft.SqlServer.Types的引用，并创建了一个包含一些dll的SqlServerTypes文件夹.
This added references to Microsoft.SqlServer.Types and created a SqlServerTypes folder that contained some dlls.
将项目重新部署到服务器后，它仍然不起作用(相同的错误).
After re-deploying the project to the server, it still doesn't work (same error).
nuget软件包中的说明说，我必须在applciaion_start事件中添加以下行:
The instructions from the nuget package say that I must add the following line to the applciaion_start event:
SqlServerTypes.Utilities.LoadNativeAssemblies(AppDomain.CurrentDomain.BaseDirectory);
我已经尝试过这样做，但是在Visual Studio中，我在SqlServerTypes下出现了一条弯曲的蓝线，错误为未声明SqlServerTypes".
I have tried doing this but I am getting squiggly blue line under SqlServerTypes with the error "SqlServerTypes is not declared" in Visual Studio.
我尝试添加
Imports Microsoft.SqlServer.Types
但是没有SqlServerTypes命名空间或类.
but there is no SqlServerTypes namespace or class.
推荐答案
nuget包Microsoft.SqlServer.Types仅适用于c#项目.
The nuget package Microsoft.SqlServer.Types is only for c# projects.
您可以修改该类以使其与vb.net项目兼容.
You can modify the class to be compatible with vb.net projects.
使用以下方法将支持安装到您的项目中:
Install support into your project using:
Install-Package Microsoft.SqlServer.Types
找到以下文件:
/SqlServerTypes/Loader.cs
将Loader.cs中的代码转换为vb(您可以使用在线转换器执行此操作)，然后将文件另存为:Loader.vb
Convert the code in Loader.cs to vb (you can do this with an online converter) and save the file as: Loader.vb
现在，您将可以从项目中访问 SqlServerTypes 命名空间.
Now you will be able to access the SqlServerTypes namespace from your project.
这篇关于SqlServer Spatial DataReader.GetFieldType返回null的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！