File.WriteAllLines(String, String) is an inbuilt File class method that is used to create a new file, writes the specified string array to the file, and then closes the file.
public static void WriteAllLines (string path, string contents);
Parameter: This function accepts two parameters which are illustrated below:
- path: This is the specified file where specified string array are going to be written.
- contents: This is the specified string array to write to the file.
- ArgumentException: The path is a zero-length string, contains only white space, or one or more invalid characters as defined by InvalidPathChars.
- ArgumentNullException: Either path or contents are null.
- PathTooLongException: The specified path, file name, or both exceed the system-defined maximum length.
- DirectoryNotFoundException: The specified path is invalid.
- IOException: An I/O error occurred while opening the file.
- UnauthorizedAccessException: The path specified a file that is read-only. OR the path specified a file that is hidden. OR this operation is not supported on the current platform. OR the path specified a directory. OR the caller does not have the required permission.
- NotSupportedException: The path is in an invalid format.
- SecurityException: The caller does not have the required permission.
Below are the programs to illustrate the File.WriteAllLines(String, String) method.
Program 1: Initially, no file was created. Below code itself create a file file.txt and write the specified string array into the file.
GFG is a CS portal.
After running the above code, the above output is shown, and a new file file.txt is created shown below-
Program 2: Initially, a file file.txt is created with some contents shown below-
Below code overwrites the file contents with the specified string array.
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After running the above code, the above output is shown, and the file file.txt contents became like shown below: