# Sandbox.SandboxSystemExtensions.GetFilenameSafe

```csharp
static string GetFilenameSafe(string input)
```

Make the passed in string filename safe. This replaces any invalid characters with "_".

### Parameters

- `input` (`string`)

### Returns

`string`

Declared in [Sandbox.SandboxSystemExtensions](/api/Sandbox.SandboxSystemExtensions).
Assembly: `Sandbox.System`.