VintaSoft Twain .NET SDK 15.1: Документация для Веб разработчика
В этом разделе
    Как получить верхнюю часть страницы от TWAIN/SANE сканера?
    В этом разделе
    Если Вы хотите установить область сканирования для TWAIN или SANE сканера, используйте функцию WebTwainDeviceJS.setImageLayout.

    Также TWAIN сканер позволяет задать область сканирования с помощью функции WebTwainDeviceJS.setCapability.

    Вот JavaScript код, который демонстрирует, как использовать функцию WebDeviceJS.setImageLayout для получения области изображения от TWAIN/SANE сканера:
    // acquire top part of page from TWAIN/SANE scanner
    __acquireTopPartOfPageFromTwainScanner();
    
    
    
    /**
     * Acquires top part of page from TWAIN/SANE scanner.
     */
    function __acquireTopPartOfPageFromTwainScanner() {
        // register the evaluation version of VintaSoft Web TWAIN service
        // please read how to get evaluation license in documentation: https://www.vintasoft.ru/docs/vstwain-dotnet-web/Licensing-Twain_Web-Evaluation.html
        Vintasoft.Twain.WebTwainGlobalSettingsJS.register('REG_USER', 'REG_URL', 'REG_CODE', 'EXPIRATION_DATE');
    
        // URL to the VintaSoft Web TWAIN service
        var serviceUrl = 'https://localhost:25329/api/VintasoftTwainApi';
        // a Web API controller that allows to work with TWAIN and SANE devices
        var twainService = new Vintasoft.Shared.WebServiceControllerJS(serviceUrl);
    
        // TWAIN/SANE device manager
        var deviceManager = new Vintasoft.Twain.WebTwainDeviceManagerJS(twainService);
    
        // the default settings of device manager
        var deviceManagerInitSetting = new Vintasoft.Twain.WebTwainDeviceManagerInitSettingsJS();
    
        var device = null;
        try {
            // open device manager
            deviceManager.open(deviceManagerInitSetting);
    
            // get the default TWAIN/SANE device
            device = deviceManager.get_DefaultDevice();
    
            // open device without UI
            device.open(false);
    
            // if device is TWAIN device
            if (device.get_DeviceName().substring(0, 5) == "Twain") {
                // set the inches as unit of measure
                device.set_UnitOfMeasure(new Vintasoft.Twain.WebUnitOfMeasureEnumJS("Inches"));
            }
            // get current image layout
            let imageLayout: Vintasoft.Twain.WebTwainImageLayoutJS = device.getImageLayout();
            // set the image layout (get only the top half of the page)
            device.setImageLayout(0, 0, imageLayout.get_Width(), imageLayout.get_Height() / 2); 
    
            var acquireModalState;
            do {
                // do one step of modal image acquisition process
                var acquireModalResult = device.acquireModalSync();
                // get state of image acquisition
                acquireModalState = acquireModalResult.get_AcquireModalState().valueOf();
    
                switch (acquireModalState) {
                    case 2:   // image is acquired
                        // get acquired image
                        var acquiredImage = acquireModalResult.get_AcquiredImage();
                        // get image as Base64 string
                        var bitmapAsBase64String = acquiredImage.getAsBase64String();
                        // update image preview
                        var previewImageElement = document.getElementById('previewImage');
                        previewImageElement.src = bitmapAsBase64String;
                        break;
                    case 4:   // image scan is failed
                        alert(acquireModalResult.get_ErrorMessage());
                        break;
                    case 9:   // image scan is finished
                        break;
                }
            }
            while (acquireModalState !== 0);
        }
        catch (ex) {
            alert(ex);
        }
        finally {
            if (device != null) {
                // close the device
                device.close();
            }
            // close the device manager
            deviceManager.close();
        }
    }
    
    


    Вот TypeScript код, который демонстрирует, как использовать функцию WebDeviceJS.setImageLayout для получения области изображения от TWAIN/SANE сканера:
    import { Component } from '@angular/core';
    
    @Component({
      selector: 'twain-scanning-demo',
      templateUrl: './twain-scanning-demo.component.html'
    })
    export class TwainScanningDemoComponent {
    
      ngOnInit() {
        // acquire top part of page from TWAIN/SANE scanner
        this.__acquireTopPartOfPageFromTwainScanner();
      }
    
    
      /**
       * Acquires top part of page from TWAIN/SANE scanner.
       */
      __acquireTopPartOfPageFromTwainScanner() {
        // register the evaluation version of VintaSoft Web TWAIN service
        // please read how to get evaluation license in documentation: https://www.vintasoft.ru/docs/vstwain-dotnet-web/Licensing-Twain_Web-Evaluation.html
        Vintasoft.Twain.WebTwainGlobalSettingsJS.register('REG_USER', 'REG_URL', 'REG_CODE', 'EXPIRATION_DATE');
    
        // URL to the VintaSoft Web TWAIN service
        let serviceUrl: string = 'https://localhost:25329/api/VintasoftTwainApi';
        // a Web API controller that allows to work with TWAIN and SANE devices
        let twainService: Vintasoft.Shared.WebServiceControllerJS = new Vintasoft.Shared.WebServiceControllerJS(serviceUrl);
    
        // TWAIN/SANE device manager
        let deviceManager: Vintasoft.Twain.WebTwainDeviceManagerJS = new Vintasoft.Twain.WebTwainDeviceManagerJS(twainService);
    
        // the default settings of device manager
        let deviceManagerInitSetting: Vintasoft.Twain.WebTwainDeviceManagerInitSettingsJS = new Vintasoft.Twain.WebTwainDeviceManagerInitSettingsJS();
    
        try {
          // open device manager
          deviceManager.open(deviceManagerInitSetting);
        }
        catch (ex) {
          alert(ex);
          return;
        }
    
        let device: Vintasoft.Twain.WebTwainDeviceJS = null;
        try {
          // get the default TWAIN/SANE device
          device = deviceManager.get_DefaultDevice();
    
          // open device without UI
          device.open(false);
    
          // if device is TWAIN device
          if (device.get_DeviceName().substring(0, 5) == "Twain") {
              // set the inches as unit of measure
              device.set_UnitOfMeasure(new Vintasoft.Twain.WebUnitOfMeasureEnumJS("Inches"));
          }
          // get current image layout
          let imageLayout: Vintasoft.Twain.WebTwainImageLayoutJS = device.getImageLayout();
          // set the image layout (get only the top half of the page)
          device.setImageLayout(0, 0, imageLayout.get_Width(), imageLayout.get_Height() / 2); 
    
          let acquireModalState: number;
          do {
            // do one step of modal image acquisition process
            let acquireModalResult: Vintasoft.Twain.WebTwainDeviceAcquireModalResultJS = device.acquireModalSync();
            // get state of image acquisition
            acquireModalState = acquireModalResult.get_AcquireModalState().valueOf() as number;
    
            switch (acquireModalState) {
              case 2:   // image is acquired
                // get acquired image
                let acquiredImage: Vintasoft.Twain.WebAcquiredImageJS = acquireModalResult.get_AcquiredImage();
                // get image as Base64 string
                let bitmapAsBase64String: string = acquiredImage.getAsBase64String();
                // update image preview
                let previewImageElement: HTMLImageElement = document.getElementById('previewImage') as HTMLImageElement;
                previewImageElement.src = bitmapAsBase64String;
                break;
              case 4:   // image scan is failed
                alert(acquireModalResult.get_ErrorMessage());
                break;
              case 9:   // image scan is finished
                break;
            }
          }
          while (acquireModalState !== 0);
        }
        catch (ex) {
          alert(ex);
        }
        finally {
          if (device != null) {
            // close the device
            device.close();
          }
          // close the device manager
          deviceManager.close();
        }
      }
    
    }
    
    



    Вот JavaScript код, который демонстрирует, как использовать функцию WebDeviceJS.setCapability для получения области изображения от TWAIN/SANE сканера:
    // acquire top part of page from TWAIN scanner
    __acquireTopPartOfPageFromTwainScanner();
    
    
    
    /**
     * Acquires top part of page from TWAIN scanner.
     */
    function __acquireTopPartOfPageFromTwainScanner() {
        // register the evaluation version of VintaSoft Web TWAIN service
        // please read how to get evaluation license in documentation: https://www.vintasoft.ru/docs/vstwain-dotnet-web/Licensing-Twain_Web-Evaluation.html
        Vintasoft.Twain.WebTwainGlobalSettingsJS.register('REG_USER', 'REG_URL', 'REG_CODE', 'EXPIRATION_DATE');
    
        // URL to the VintaSoft Web TWAIN service
        var serviceUrl = 'https://localhost:25329/api/VintasoftTwainApi';
        // a Web API controller that allows to work with TWAIN and SANE devices
        var twainService = new Vintasoft.Shared.WebServiceControllerJS(serviceUrl);
    
        // TWAIN device manager
        var deviceManager = new Vintasoft.Twain.WebTwainDeviceManagerJS(twainService);
    
        // the default settings of device manager
        var deviceManagerInitSetting = new Vintasoft.Twain.WebTwainDeviceManagerInitSettingsJS();
    
        var device = null;
        try {
            // open device manager
            deviceManager.open(deviceManagerInitSetting);
    
            // get the default TWAIN device
            device = deviceManager.get_DefaultDevice();
    
            // open device without UI
            device.open(false);
    
            // set the inches as unit of measure
            device.set_UnitOfMeasure(new Vintasoft.Twain.WebUnitOfMeasureEnumJS("Inches"));
            // set the image layout rectangle as value of IFrames capability
            device.setCapability(new Vintasoft.Twain.WebDeviceCapabilityIdEnumJS("IFrames"), new Vintasoft.Twain.WebTwainFrameJS(0, 0, 2, 2));
    
            var acquireModalState;
            do {
                // do one step of modal image acquisition process
                var acquireModalResult = device.acquireModalSync();
                // get state of image acquisition
                acquireModalState = acquireModalResult.get_AcquireModalState().valueOf();
    
                switch (acquireModalState) {
                    case 2:   // image is acquired
                        // get acquired image
                        var acquiredImage = acquireModalResult.get_AcquiredImage();
                        // get image as Base64 string
                        var bitmapAsBase64String = acquiredImage.getAsBase64String();
                        // update image preview
                        var previewImageElement = document.getElementById('previewImage');
                        previewImageElement.src = bitmapAsBase64String;
                        break;
                    case 4:   // image scan is failed
                        alert(acquireModalResult.get_ErrorMessage());
                        break;
                    case 9:   // image scan is finished
                        break;
                }
            }
            while (acquireModalState !== 0);
        }
        catch (ex) {
            alert(ex);
        }
        finally {
            if (device != null) {
                // close the device
                device.close();
            }
            // close the device manager
            deviceManager.close();
        }
    }
    
    


    Вот TypeScript код, который демонстрирует, как использовать функцию WebDeviceJS.setCapability для получения области изображения от TWAIN/SANE сканера:
    import { Component } from '@angular/core';
    
    @Component({
      selector: 'twain-scanning-demo',
      templateUrl: './twain-scanning-demo.component.html'
    })
    export class TwainScanningDemoComponent {
    
      ngOnInit() {
        // acquire top part of page from TWAIN scanner
        this.__acquireTopPartOfPageFromTwainScanner();
      }
    
    
      /**
       * Acquires top part of page from TWAIN scanner.
       */
      __acquireTopPartOfPageFromTwainScanner() {
        // register the evaluation version of VintaSoft Web TWAIN service
        // please read how to get evaluation license in documentation: https://www.vintasoft.ru/docs/vstwain-dotnet-web/Licensing-Twain_Web-Evaluation.html
        Vintasoft.Twain.WebTwainGlobalSettingsJS.register('REG_USER', 'REG_URL', 'REG_CODE', 'EXPIRATION_DATE');
    
        // URL to the VintaSoft Web TWAIN service
        let serviceUrl: string = 'https://localhost:25329/api/VintasoftTwainApi';
        // a Web API controller that allows to work with TWAIN and SANE devices
        let twainService: Vintasoft.Shared.WebServiceControllerJS = new Vintasoft.Shared.WebServiceControllerJS(serviceUrl);
    
        // TWAIN device manager
        let deviceManager: Vintasoft.Twain.WebTwainDeviceManagerJS = new Vintasoft.Twain.WebTwainDeviceManagerJS(twainService);
    
        // the default settings of device manager
        let deviceManagerInitSetting: Vintasoft.Twain.WebTwainDeviceManagerInitSettingsJS = new Vintasoft.Twain.WebTwainDeviceManagerInitSettingsJS();
    
        try {
          // open device manager
          deviceManager.open(deviceManagerInitSetting);
        }
        catch (ex) {
          alert(ex);
          return;
        }
    
        let device: Vintasoft.Twain.WebTwainDeviceJS = null;
        try {
          // get the default TWAIN device
          device = deviceManager.get_DefaultDevice();
    
          // open device without UI
          device.open(false);
    
          // set the inches as unit of measure
          device.set_UnitOfMeasure(new Vintasoft.Twain.WebUnitOfMeasureEnumJS("Inches"));
          // set the image layout rectangle as value of IFrames capability
          device.setCapability(new Vintasoft.Twain.WebDeviceCapabilityIdEnumJS("IFrames"), new Vintasoft.Twain.WebTwainFrameJS(0, 0, 2, 2));
    
          let acquireModalState: number;
          do {
            // do one step of modal image acquisition process
            let acquireModalResult: Vintasoft.Twain.WebTwainDeviceAcquireModalResultJS = device.acquireModalSync();
            // get state of image acquisition
            acquireModalState = acquireModalResult.get_AcquireModalState().valueOf() as number;
    
            switch (acquireModalState) {
              case 2:   // image is acquired
                // get acquired image
                let acquiredImage: Vintasoft.Twain.WebAcquiredImageJS = acquireModalResult.get_AcquiredImage();
                // get image as Base64 string
                let bitmapAsBase64String: string = acquiredImage.getAsBase64String();
                // update image preview
                let previewImageElement: HTMLImageElement = document.getElementById('previewImage') as HTMLImageElement;
                previewImageElement.src = bitmapAsBase64String;
                break;
              case 4:   // image scan is failed
                alert(acquireModalResult.get_ErrorMessage());
                break;
              case 9:   // image scan is finished
                break;
            }
          }
          while (acquireModalState !== 0);
        }
        catch (ex) {
          alert(ex);
        }
        finally {
          if (device != null) {
            // close the device
            device.close();
          }
          // close the device manager
          deviceManager.close();
        }
      }
    
    }