---
id: "P:cAlgo.API.SaveFileDialog.DefaultExt"
kind: "property"
type: "T:cAlgo.API.SaveFileDialog"
url: "https://help.ctrader.com/ctrader-algo/references/Dialogs/SaveFileDialog/DefaultExt/"
---

> Documentation index for agents: https://help.ctrader.com/ctrader-algo/llms.txt · machine index: https://help.ctrader.com/ctrader-algo/api.json

# SaveFileDialog.DefaultExt

Member of [SaveFileDialog](https://help.ctrader.com/ctrader-algo/references/Dialogs/SaveFileDialog/index.md).

## DefaultExt

Gets or sets a value that specifies the default extension string to use to filter the list of files that are displayed.

Environments: Desktop supported · CLI not supported · Cloud not supported.

- CLI: No dialog can be shown in the CLI: ShowDialog returns FileDialogResult.None, nothing is written and the dialog settings are only stored.
- Cloud: No dialog can be shown in the cloud: ShowDialog returns FileDialogResult.None, nothing is written and the dialog settings are only stored.

C#:

```csharp
public string DefaultExt {get; set;}
```

Python:

```python
saveFileDialog.DefaultExt: str
```

### Returns

`string` — 

Available since cAlgo.API 5.1.

### Examples

C#:

```csharp
var saveFileDialog = new SaveFileDialog { DefaultExt = "csv", Filter = "CSV files (*.csv)|*.csv" };
saveFileDialog.ShowDialog();
Print("Default extension: {0}", saveFileDialog.DefaultExt);
```

Python:

```python
saveFileDialog = SaveFileDialog()
saveFileDialog.DefaultExt = "csv"
saveFileDialog.Filter = "CSV files (*.csv)|*.csv"
saveFileDialog.ShowDialog()
api.Print(f"Default extension: {saveFileDialog.DefaultExt}")
```