Maui - FilePicker - Return TextFile FullPath Asynchronously - maui

Question

The goal is to have a Maui class library that will have a function that return a full path to read a text file in my Maui application.
Can you help me to fix the following code?
The error is when I try to return the FullPath as string
var FileFullPath = await result.FullPath.ToString();
Here the error description
Severity Code Description Project File Line Suppression State Error CS1061
'string' does not contain a definition for 'GetAwaiter' and no accessible extension method 'GetAwaiter' accepting a first argument of type 'string' could be found (are you missing a using directive or an assembly reference?) MPCFilePickerMauiLibrary (net7.0), MPCFilePickerMauiLibrary (net7.0-android), MPCFilePickerMauiLibrary (net7.0-ios), MPCFilePickerMauiLibrary (net7.0-maccatalyst) D:\repos\MPC-MassPropertiesCalculator\MPCFilePickerMauiLibrary\PickTxtFile.cs 35 Active
Here is the Maui class library that have created.
using Microsoft.Maui.Storage;
namespace MPCFilePickerMauiLibrary;
//Ref https://youtu.be/C6LV_xMGdKc - Intro To Class Libraries in C#
public class PickTxtFile
{
public static async Task<string> GetFilePathAsync()
{
//For custom file types
var customFileType = new FilePickerFileType(
new Dictionary<DevicePlatform, IEnumerable<string>>
{
{ DevicePlatform.iOS, new[] { "public.text" } }, // UTType values
{ DevicePlatform.Android, new[] { "text/plain" } }, // MIME type
{ DevicePlatform.WinUI, new[] { ".Txt" } }, // file extension
{ DevicePlatform.Tizen, new[] { "*/*" } },
{ DevicePlatform.macOS, new[] { "Txt" } }, // UTType values
});
var result = await FilePicker.PickAsync(new PickOptions
{
PickerTitle = "Pick MPC Demo file Please",
FileTypes = customFileType
});
if (result == null)
return "";
var FileFullPath = await result.FullPath.ToString();
return FileFullPath;
}
Here is the code where I'm using the function
using MPCFilePickerMauiLibrary;
using Microsoft.UI.Xaml.Controls;
namespace MPC_MassPropertiesCalculator_MAUIapp.Views;
public partial class MPCFileDemo : ContentPage
{
public MPCFileDemo()
{
InitializeComponent();
}
private void MenuFlyoutItem_Clicked(object sender, EventArgs e)
{
String filePath = PickTxtFile.GetFilePathAsync();
if (File.Exists(filePath))
{
//TODO Read file
}
}
}

Answer 1

With Jason's comments, here is the solution.
Maui class library
using Microsoft.Maui.Storage;
namespace MPCFilePickerMauiLibrary;
//Ref https://youtu.be/C6LV_xMGdKc - Intro To Class Libraries in C#
public class PickTxtFile
{
public static async Task<string> GetFilePathAsync()
{
//For custom file types
var customFileType = new FilePickerFileType(
new Dictionary<DevicePlatform, IEnumerable<string>>
{
{ DevicePlatform.iOS, new[] { "public.text" } }, // UTType values
{ DevicePlatform.Android, new[] { "text/plain" } }, // MIME type
{ DevicePlatform.WinUI, new[] { ".Txt" } }, // file extension
{ DevicePlatform.Tizen, new[] { "*/*" } },
{ DevicePlatform.macOS, new[] { "Txt" } }, // UTType values
});
var result = await FilePicker.PickAsync(new PickOptions
{
PickerTitle = "Pick MPC Demo file Please",
FileTypes = customFileType
});
if (result == null)
return "";
var FileFullPath = result.FullPath.ToString();
return FileFullPath;
}
}
Code in the application
using MPCFilePickerMauiLibrary;
namespace MPC_MassPropertiesCalculator_MAUIapp.Views;
public partial class MPCFileDemo : ContentPage
{
public MPCFileDemo()
{
InitializeComponent();
}
private async void MenuFlyoutItem_Clicked(object sender, EventArgs e)
{
string? filePath = await PickTxtFile.GetFilePathAsync();
if (File.Exists(filePath))
{
await DisplayAlert("File Path", $"File Path is: {filePath}", "OK");
}
else
{
await DisplayAlert("File Path", "Usre did not select a file", "OK");
}
}
}
Output result image.