At the end of the data that you concatenate together, you add Environment. This adds a line break a newline character. What you're creating with all this concatenation is a string that looks like this:. You then create a variable dataFile that contains the location and name of the file to store the data in.
Setting the location requires some special handling. If a website is moved, an absolute path will be wrong. Moreover, for a hosted site as opposed to on your own computer you typically don't even know what the correct path is when you're writing the code.
But sometimes like now, for writing a file you do need a complete path. The solution is to use the MapPath method of the Server object. This returns the complete path to your website.
You can then concatenate additional information onto whatever the method returns in order to create a complete path. In this example, you add a file name. You can read more about how to work with file and folder paths in Introduction to ASP. This folder is a special folder in ASP. The WriteAllText method of the File object writes the data to the file. This method takes two parameters: the name with path of the file to write to, and the actual data to write. Notice that the name of the first parameter has an character as a prefix.
This tells ASP. For more information, see Introduction to ASP. On your development computer this is not typically an issue. However, when you publish your site to a hosting provider's web server, you might need to explicitly set those permissions.
If you run this code on a hosting provider's server and get errors, check with the hosting provider to find out how to set those permissions. In the previous example, you used WriteAllText to create a text file that's got just one piece of data in it. If you call the method again and pass it the same file name, the existing file is completely overwritten.
However, after you've created a file you often want to add new data to the end of the file. You can do that using the AppendAllText method of the File object. In the website, make a copy of the UserData. This code has one change in it from the previous example. The methods are similar, except that AppendAllText adds the data to the end of the file. Even if you don't need to write data to a text file, you'll probably sometimes need to read data from one. To do this, you can again use the File object.
You can use the File object to read each line individually separated by line breaks or to read individual item no matter how they're separated. This procedure shows you how to read and display the data that you created in the previous example. The code starts by reading the file that you created in the previous example into a variable named userData , using this method call:.
The code to do this is inside an if statement. When you want to read a file, it's a good idea to use the File. Exists method to determine first whether the file is available. The code also checks whether the file is empty. The body of the page contains two foreach loops, one nested inside the other. The outer foreach loop gets one line at a time from the data file. In this case, the lines are defined by line breaks in the file — that is, each data item is on its own line.
The inner loop splits each data line into items fields using a comma as a delimiter. Based on the previous example, this means that each line contains three fields — the first name, last name, and email address, each separated by a comma. The code illustrates how to use two data types, an array and the char data type. The array is required because the File.
ReadAllLines method returns data as an array. The char data type is required because the Split method returns an array in which each element is of the type char. Visible: This property determines whether the control will be displayed on the UI or hidden. The default is true. Step 1: Create a new ASP. Net WebApplication project. This will create a shell template with a working application with a Default. Step 2: Go to the Default.
Step 3. Find the FileUpload control and drag it in the Default. Net FileUpload tag in your Default. Modify the code to look like below. Make sure the directory path is correct. Please try again. Step 7: Run the application. Below is the output of your code. It has a file upload control that allows users to browse and select a file from the local storage.
The code-behind file has a SaveAs function to the FileUpload object. This method uploads the contents of the file and saves them to the specified directory. The above is the landing page of your application. Choose a file by clicking on the Choose File button. Once you have chosen a file, the file name is displayed alongside the FileUpoad control.
This method contains the SaveAs call to the server. Notice that the file is indeed saved at the specified path in the server. In our case, our local storage is the server as we are running the application on localhost. Net Button1. Add "onclick","return checkFileExt 'csvUpload' ; return false;".
Wednesday, February 18, AM. User posted you can not put the restriction on selected file.. User posted Hello nnsandhya, Sorry, that's not possible. User posted ok.. Thanks Rick For the immediate response. I am new to.
NET and thought its possible. Thank you User posted Thanks Jwalin, for the quick response.
0コメント