BarcodeScanner.ClaimScannerAsync 方法

定义

命名空间:

Windows.Devices.PointOfService

尝试获取对条形码扫描仪的独占访问权限。

public:
 virtual IAsyncOperation<ClaimedBarcodeScanner ^> ^ ClaimScannerAsync() = ClaimScannerAsync;

/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncOperation<ClaimedBarcodeScanner> ClaimScannerAsync();

[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncOperation<ClaimedBarcodeScanner> ClaimScannerAsync();

function claimScannerAsync()

Public Function ClaimScannerAsync () As IAsyncOperation(Of ClaimedBarcodeScanner)

返回

IAsyncOperation<ClaimedBarcodeScanner>

方法完成后，它将返回 ClaimedBarcodeScanner。

属性

RemoteAsyncAttribute

示例

// Claims the barcode scanner for exclusive use
task<void> Scenario1::ClaimScanner()
{
    return create_task(scanner->ClaimScannerAsync()).then([this] (ClaimedBarcodeScanner^ _claimedScanner)
    {
        this->claimedScanner = _claimedScanner;
        if (claimedScanner != nullptr)
        {
            // UpdateOutput("Barcode scanner claimed successfully.");		
        }
        else
        {
            // UpdateOutput("Failed to claim barcode scanner.");
        }
    });
}

// Claims the barcode scanner for exclusive use. 

private async Task<bool> ClaimScanner()
{
    if (claimedScanner == null)
    {
        claimedScanner = await scanner.ClaimScannerAsync();

        if (claimedScanner != null)
        {
            // UpdateOutput("Barcode scanner claimed successfully.");
           
        }
        else
        {
            // UpdateOutput("Failed to claim the barcode scanner.");
            return false;
        }
    }
    return true;
}

另请参阅

• 条形码扫描仪示例 (Windows 10)