# OpenFileDialog

Namespace: **Wisej.Web**

Assembly: **Wisej.Framework** (3.0.0.0)

* [CommonDialog](/api/v3.0/wisej.web/common-dialogs/wisej.web.commondialog.md)
  * [FileDialog](/api/v3.0/wisej.web/common-dialogs/wisej.web.filedialog.md)
    * [OpenFileDialog](/api/v3.0/wisej.web/common-dialogs/wisej.web.openfiledialog.md)

Prompts the user to open a file from the server.

{% tabs %}
{% tab title="C#" %}

```csharp
public class OpenFileDialog : FileDialog
```

{% endtab %}

{% tab title="VB.NET" %}

```visual-basic
Public Class OpenFileDialog
    Inherits FileDialog
```

{% endtab %}
{% endtabs %}

You can:

* Override [PromptFileNotFound](/api/v3.0/wisej.web/common-dialogs/wisej.web.filedialog.md#promptfilenotfound). It's called when the specified file doesn't exist and the property [CheckFileExists](#checkfileexists) is true.
* Override [CreateUI](/api/v3.0/wisej.web/common-dialogs/wisej.web.filedialog.md#createui) to create your custom [Form](/api/v3.0/wisej.web/containers/form.md) when the method [ShowDialog](/api/v3.0/wisej.web/common-dialogs/wisej.web.commondialog.md#showdialog) is called.
* Set the [DialogTemplate](/api/v3.0/wisej.web/common-dialogs/wisej.web.commondialog.md#dialogtemplate) to a [Form](/api/v3.0/wisej.web/containers/form.md) class that has a constructor that accepts [FileDialog](/api/v3.0/wisej.web/common-dialogs/wisej.web.filedialog.md) as the single argument to change the User Interface (UI) of the file dialog.
* Override [OnFileOk](/api/v3.0/wisej.web/common-dialogs/wisej.web.filedialog.md#onfileok) to provide your custom implementation of the actions to execute when the user presses the OK button.

You must add at least one [IFileSystemProvider](/api/v3.0/wisej.core/general/wisej.core.ifilesystemprovider.md) to the [Roots](/api/v3.0/wisej.web/common-dialogs/wisej.web.filedialog.md#roots) collection before showing the dialog.

## Constructors

### ![](/files/uCY6T77rh488FWHzpJ6P)OpenFileDialog()

Initializes a new instance of [OpenFileDialog](/api/v3.0/wisej.web/common-dialogs/wisej.web.openfiledialog.md).

### ![](/files/uCY6T77rh488FWHzpJ6P)OpenFileDialog(container)

Initializes a new instance of the [OpenFileDialog](/api/v3.0/wisej.web/common-dialogs/wisej.web.openfiledialog.md) extender with a specified container.

| Name          | Type                                                                                       | Description                                                                                                                                                                                                                    |
| ------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| **container** | [IContainer](https://docs.microsoft.com/en-us/dotnet/api/system.componentmodel.icontainer) | An [IContainer](https://docs.microsoft.com/en-us/dotnet/api/system.componentmodel.icontainer) that represents the container of the [OpenFileDialog](/api/v3.0/wisej.web/common-dialogs/wisej.web.openfiledialog.md) component. |

## Properties

### ![](/files/uCY6T77rh488FWHzpJ6P)CheckFileExists

[Boolean](https://docs.microsoft.com/en-us/dotnet/api/system.boolean): Returns or sets a value indicating whether the dialog box displays a warning if the user specifies a file name that does not exist.

### ![](/files/uCY6T77rh488FWHzpJ6P)Multiselect

[Boolean](https://docs.microsoft.com/en-us/dotnet/api/system.boolean): Returns or sets a value indicating whether the dialog box allows multiple files to be selected.

### ![](/files/uCY6T77rh488FWHzpJ6P)SafeFileName

[String](https://docs.microsoft.com/en-us/dotnet/api/system.string): Returns the file name and extension for the file selected in the dialog box. The file name does not include the path.

### ![](/files/uCY6T77rh488FWHzpJ6P)SafeFileNames

[String\[\]](https://docs.microsoft.com/en-us/dotnet/api/system.string): Returns an array of file names and extensions for all the selected files in the dialog box. The file names do not include the path.

## Methods

### ![](/files/uCY6T77rh488FWHzpJ6P)OpenFile()

Opens the file selected by the user, with read-only permission. The file is specified by the [FileName](/api/v3.0/wisej.web/common-dialogs/wisej.web.filedialog.md#filename) property.

**Returns:** [Stream](https://docs.microsoft.com/en-us/dotnet/api/system.io.stream). A [Stream](https://docs.microsoft.com/en-us/dotnet/api/system.io.stream) that specifies the read-only file selected by the user.

**Throws:**

* [ArgumentNullException](https://docs.microsoft.com/en-us/dotnet/api/system.argumentnullexception) [FileName](/api/v3.0/wisej.web/common-dialogs/wisej.web.filedialog.md#filename) is empty or null.

### ![](/files/uCY6T77rh488FWHzpJ6P)Reset()

Resets all properties to their default values.


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