Registering Dependency injection AddDbContext. In this part, we are going to register DatabaseContext class as a service for using it as dependency injection, which will be available to the entire application. We are going to register this service in ConfigureServices Method of startup class. First, we need to read connection string from appsettings. Getting Connection String from appsettings. Next, we are going to use AddDbContext extension method to register the DatabaseContext in the dependency injection container.
This method is backwards-compatible to SQL Server then register below method. ConfigureServices Method in Startup Class. Now we can use DatabaseContext class as service for dependency injection in the entire application.
The next step we are going to add a controller. We are going to add a controller with Name Demo Controller after adding controller we have default Index action method in it.
And also, for accessing DatabaseContext in DemoController, we are going to use Constructor injection. Next step we are going to valid Length of the posted file if it is greater then zero then we are going generate new file name, and then next we are going to create object of Files class and assign IformFile values to files object which we have created and then we are going to pass Files Model to Add method of DbContext which set entity set to Added When we call context.
SaveChanges then an Insert statement is generated and executed by the database. For example, you can provide a button that the user clicks to upload the file. The code that you write to save the specified file should call the SaveAs method, which saves the contents of a file to a specified path on the server.
Typically, the SaveAs method is called in an event-handling method for an event that raises a post back to the server. For example, if you provide a button to submit a file, the code to save the file to the server could then be included inside the event-handling method for the click event.
When you call the SaveAs method, you must specify the full path of the directory on the server in which to save the uploaded file. If you do not explicitly specify a path in your application code, an HttpException exception is thrown when a user attempts to upload a file. This behavior helps keep the files on the server secure, by not allowing users to specify a path in which to save the files that they upload. Before calling the SaveAs method, you should use the HasFile property to verify that the FileUpload control contains a file to upload.
If the HasFile returns true , call the SaveAs method. If it returns false , display a message to the user indicating that the control does not contain a file. If you do not provide error-handling code to verify that a file exists, an attempt to save a nonexistent file throws an HttpException exception.
NET application must have write access to the directory on the server. There are two ways that the application can get write access. You can explicitly grant write access to the account under which the application is running, in the directory in which the uploaded files will be saved.
Alternatively, you can increase the level of trust that is granted to the ASP. NET application. Upload control. Stream fs File. Stream Binary. Reader br new. Readerfs byte bytes br. Length Save the Byte Array as File.
Path Files Path. How to create a pdf file in C PDF Portable Document Format is a file format that has replicate all the characteristics of a printed document that you can read. Name File. Path, bytes Display the Image File. Url file. Path Image. Visible true VB. Sub btn. UploadClicksender As. Object, e As. Dim fs As. Stream File.
0コメント