# FileHelper `FileHelper` class provides synchronous and asynchronous methods for the write, read and delete a single file. ## SaveFile() Synchronously saves a byte array to a file by an absolute path. ```csharp FileHelper.SaveFile("absolute_file_path", bytes); ``` By default, if the file exists, the `FileHelper` creates a new file with a unique name and returns that name. ```csharp string existingFilePath = "D:\\readme.txt"; string newFilePath = FileHelper.SaveFile(existingFilePath, bytes); // Returns "D:\\readme_1.txt". ``` All parameters: | Param name | Param type | Description | | ----------------------------- | ---------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------ | | path | `string` | The absolute file path to save to. | | bytes | `byte[]` | The bytes to save to the file. | | createDirIfNotExists | `bool` | The flag indicates to create destination directory if not exists. Default value is `true`. | | useSequentialFileNameIfExists | `bool` | The flag indicates that target file name should be changed by adding sequential postfix if file with specfied name already exists. Default value is `false`. | ## SaveFileAsync() Asynchronously saves a byte array to a file by an absolute path. ```csharp await FileHelper.SaveFileAsync("absolute_file_path", bytes); ``` By default, if the file exists, the `FileHelper` creates a new file with a unique name and returns that name. ```csharp string existingFilePath = "D:\\readme.txt"; string newFilePath = await FileHelper.SaveFileAsync(existingFilePath, bytes); // Returns "D:\\readme_1.txt". ``` All parameters: | Param name | Param type | Description | | ----------------------------- | ------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------ | | path | `string` | The absolute file path to save to. | | bytes | `byte[]` | The bytes to save to the file. | | createDirIfNotExists | `bool` | The flag indicates to create destination directory if not exists. Default value is `true`. | | useSequentialFileNameIfExists | `bool` | The flag indicates that target file name should be changed by adding sequential postfix if file with specfied name already exists. Default value is `false`. | | cancellationToken | `CancellationToken` | The token to monitor for cancellation requests. Default value is `None`. | ## ReadFile() Synchronously reads a file from an absolute path to a byte array. ```csharp byte[] bytes = FileHelper.ReadFile(filePath); ``` All parameters: | Param name | Param type | Description | | ---------------- | ---------- | ---------------------------------------------------------------------------------- | | path | `string` | The absolute file path to read to. | | throwIfNotExists | `bool` | The flag indicates to throw exception if file not exists. Default value is `true`. | You can also synchronously reads a file from a stream to a byte array. ```csharp byte[] bytes = FileHelper.ReadFile(stream); ``` All parameters: | Param name | Param type | Description | | ------------- | ---------- | ----------------------------------------------------- | | stream | `Stream` | The Stream (MemoryStream, FileStream, etc.). | | initialLength | `long` | Length of returning byte array. Default value is `0`. | ## ReadFileAsync() Asynchronously reads a file from an absolute path to a byte array. ```csharp byte[] bytes = await FileHelper.ReadFileAsync(filePath); ``` All parameters: | Param name | Param type | Description | | ----------------- | ------------------- | ---------------------------------------------------------------------------------- | | path | `string` | The absolute file path to read to. | | throwIfNotExists | `bool` | The flag indicates to throw exception if file not exists. Default value is `true`. | | cancellationToken | `CancellationToken` | The token to monitor for cancellation requests. Default value is `None`. | You can also asynchronously reads a file from a stream to a byte array. ```csharp byte[] bytes = await FileHelper.ReadFileAsync(stream); ``` All parameters: | Param name | Param type | Description | | ----------------- | ------------------- | ------------------------------------------------------------------------ | | stream | `Stream` | The Stream (MemoryStream, FileStream, etc.). | | initialLength | `long` | Length of returning byte array. Default value is `0`. | | cancellationToken | `CancellationToken` | The token to monitor for cancellation requests. Default value is `None`. | ## DeleteFile() Deletes a file if it exists. ```csharp FileHelper.DeleteFile(filePath); ``` All parameters: | Param name | Param type | Description | | ---------- | ---------- | ------------------------------------ | | path | `string` | The absolute file path to delete to. | ## GetFilePathWithSequentialFileName() Returns an absolute path with variable destination file name with sequential postfix e.g. ("file\_1.txt", "file\_2.txt"). ```csharp string existingFilePath = "D:\\readme.txt"; string newFilePath = FileHelper.GetFilePathWithSequentialFileName(existingFilePath); // Returns "D:\\readme_1.txt". ``` All parameters: | Param name | Param type | Description | | ---------- | ---------- | ----------------------- | | path | `string` | The absolute file path. | --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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