在Azure App Service for Windows的环境中,部署.NET应用,其中使用了 SAP NetWeaver RFC函数 (需要加载 sapnwrfc.dll)。详细的错误为:
“System.DllNotFoundException: Unable to load DLL 'sapnwrfc' or one of its dependencies: The specified module could not be found. (0x8007007E)”
那么在App Service中如何来解决这个问题呢?
在App Service的日志中,除了可见”System.DllNotFoundException: Unable to load DLL 'sapnwrfc' or one of its dependencies: The specified module could not be found“外,也显示 Could not open the ICU common library。如下图:
在App Service不能加载ICU通用库的提示下,就需要在代码中显示的加载ICU库。所以在代码中添加 NativeLibrary.Load(path.Combinee(rootDir, "nwrfcsdk", "icuin50")) 即可缓解问题。
代码示例为:
using System.Reflection; using System.Runtime.InteropServices; using NwRfcNet; namespace CallSAPonAppService { public class Program { public static void Main(string[] args) { var builder = WebApplication.CreateBuilder(args); // Add services to the container. builder.Services.AddControllers(); // Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle builder.Services.AddEndpointsApiExplorer(); builder.Services.AddSwaggerGen(); var app = builder.Build(); // Configure the HTTP request pipeline. if (app.Environment.IsDevelopment()) { app.UseSwagger(); app.UseSwaggerUI(); } app.UseHttpsRedirection(); app.UseAuthorization(); app.MapControllers(); NativeLibrary.SetDllImportResolver( assembly: typeof(RfcConnection).Assembly, resolver: (string libraryName, Assembly assembly, DllImportSearchPath? searchPath) => { if (libraryName == "sapnwrfc") { var rootDir = System.IO.Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location); string path = Path.Combine(rootDir, "nwrfcsdk", libraryName); //手动加载ICU库 NativeLibrary.Load(path.Combinee(rootDir, "nwrfcsdk", "icuuc50")); NativeLibrary.Load(path.Combinee(rootDir, "nwrfcsdk", "icudt50")); NativeLibrary.Load(path.Combinee(rootDir, "nwrfcsdk", "icuin50")); NativeLibrary.TryLoad( libraryPath: path, handle: out IntPtr handle); return handle; } return IntPtr.Zero; }); app.Run(); } } }
如查看是否安装Visual C++ 2013 Redistributable依赖,可以使用如下命令:
reg query "HKLM\SOFTWARE\Classes\Installer\Dependencies\{61087a79-ac85-455c-934d-1fa22cc64f36}"
查看结果如图
SapConnection connect issues #5 : https://github.com/huysentruitw/SapNwRfc/issues/5