How do I create directory if it doesn’t exist to create a file?

To Create

(new FileInfo(filePath)).Directory.Create() before writing to the file.

….Or, if it exists, then create (else do nothing)

System.IO.FileInfo file = new System.IO.FileInfo(filePath);
file.Directory.Create(); // If the directory already exists, this method does nothing.
System.IO.File.WriteAllText(file.FullName, content);