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Table of contents

Dynamsoft.WebTwainEnv

Global properties and functions.

interface Dynamsoft.WebTwainEnv {
    readonly ActiveXVersion: string;
    readonly JSVersion: string;
    readonly PdfVersion: string;
    readonly ServerLinuxVersionInfo: string;
    readonly ServerMacVersionInfo: string;
    readonly ServerVersionInfo: string;
    /**
     * Whether to create a WebTwain instance automatically.
     */
    AutoLoad: boolean;
    ContainerMap: object;
    /**
     * Define the Id and UI of the WebTwain instances.
     */
    Containers: Container[];
    Host: string; //"local.dynamsoft.com"
    IfAddMD5InUploadHeader: boolean;
    IfDisableDefaultSettings: boolean;
    IfUseActiveXForIE10Plus: boolean;
    readonly inited: boolean;
    ProductKey: string;
    ResourcesPath: string;
    UseLocalService: boolean;
    UseDefaultInstallUI: boolean;
    
    // Functions
    CreateDWTObject(
        ContainerId: string, 
        host?: string, 
        port?: string | number, 
        portSSL?: string | number, 
        asyncSuccessFunc: function (DWObject: WebTwain) {}, 
        asyncFailureFunc: function (errorString: string) {}
    ): void;
    CreateDWTObjectEx(
        dwtInitialConfig: DWTInitialConfig,                 
        asyncSuccessFunc: (DWObject: WebTwain) => {},                   
        asyncFailureFunc: (errorString: string) => {}
    ): void;
    DeleteDWTObject(Id?: string): boolean;
    GetWebTwain(ContainerId?: string): WebTwain;
    GetWebTwainEx(WebTwainId: string): WebTwain;
    Load(): void;
    Unload(): void;
    RemoveAllAuthorizations: function () {};
    OnWebTwainNotFound: function () {};
    OnWebTwainPostExecute: function () {};
    OnWebTwainPreExecute: function () {};
    OnWebTwainReady: function () {};
    OnWebTwainWillInit: function () {};
    UseDefaultViewer: boolean;
    CustomizableDisplayInfo: CustomizableDisplayInfo;
    WasmConfig: WasmConfig;
}
interface CustomizableDisplayInfo {
  // Specify the source of the loader bar.
  loaderBarSource: string;
  loaderBarClassName: string;
}
interface WasmConfig {
  maxHeapSize: number;
  fetchOptions: fetchOptions;
}
interface fetchOptions {
  headers: HeadersInit;
  mode: RequestMode;
  credentials: RequestCredentials;
}

Options

Containers

An array of Container definitions that specifies the UI elements for WebTwain instances. The Container interface is defined below

interface Container {
    WebTwainId?: string, // Id of the WebTwain instance
    ContainerId?: string, // Id of the element
    Width?: string | number, // Width of the element
    Height?: string | number // Height of the element
}

WebTwainId and ContainerId are both optional but one must exist as the identifier for that WebTwain instance.

Width and Height determine the initial viewer size of the instance.

IfAddMD5InUploadHeader

Whether or not an md5 header dwt-md5 should be included in HTTP upload requests. Note that this header is not a standard header and may be deemed invalid on some web servers.

The default value is false .

ProductKey

Sets or returns the product key for the library. A product key is required to enables certain modules of the library.

ResourcesPath

Sets or returns where the library looks for resources files including service installers, CSS, etc.

UseLocalService

Sets or returns whether to use the service or use WASM only. This property can be changed at runtime (but not recommended) and affects WebTwain instances created after the change.

The default value is true .

Functions

CreateDWTObject()

Creates a new WebTwain instance that listens to the specified host & ports. An UI element specified by the parameter ContainerId which is typically a <div> is required. The library will generate a UI and bind it to this element.

CreateDWTObjectEx()

Creates a new UI-less WebTwain instance. This instance will be uniquely identified by the parameter WebTwainId .

interface DWTInitialConfig {
  WebTwainId: string;
  Host ? : string;
  Port ? : string;
  PortSSL ? : string;
  UseLocalService?: boolean;
}

DeleteDWTObject()

Delete the WebTwain instance specified by Id which can either be a ContainerId or a WebTwainId .

GetWebTwain()

Gets an WebTwain instance by its ContainerId .

GetWebTwainEx()

Gets an WebTwain instance by its WebTwainId .

Load()

Initiates the library. If there are predefined Containers , one WebTwain instance will be created for each Container .

RegisterEvent()

Registers an environmental event. Typically the event is OnWebTwainReady which is triggered when the initialization completes.

Unload()

Destroys all WebTwain instances and cuts off the connection to the Dynamsoft Service.

RemoveAllAuthorizations()

Removes the specific authorizations made by end users on a client machine. Only effective when the security feature is enabled for local files, scanners or cameras.

UseDefaultViewer

Whether to use the built-in viewer. If it is set to false , the file dynamsoft.viewer.js is not loaded at all and there is no way to add it back later. Therefore, only set it to false when you absolutely won’t need the viewer or will be building your own viewer.

CustomizableDisplayInfo

Use this API to customize the UI.

errorMessages

Specify the error messages.

generalMessages

Specify general messages.

customProgressText

Specify text on progress bars.

buttons

Specify the titles and whether to show one or multiple buttons on the image editor.

dialogText

Specify the text on dialogs.

loaderBarSource

Specify the source of the loader bar image. Check out more on HTMLImageElement.src.

loaderBarClassName

Specify the class name of the DIV element that contains the loader bar. With this class, you can customize the loader bar even further with CSS.

WasmConfig

maxHeapSize

Specify the maximum memory allowed to be used by the library when it’s in WASM-mode. By default, it’s 200 (MB).

fetchOptions

  • headers

A Headers object, an object literal, or an array of two-item arrays to set request’s headers. Check out HeadersInit.

  • mode

A string to indicate whether the request will use CORS, or will be restricted to same-origin URLs. Sets request’s mode. Check out RequestMode.

  • credentials

A string indicating whether credentials will be sent with the request always, never, or only when sent to a same-origin URL. Sets request’s credentials. Check out RequestCredentials.

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