Mht C Reference Documentation
Mht
Current Version: 10.1.0
Chilkat MHT can generate email objects from HTML files and URLs, and convert HTML to MHT or EML files.
Create/Dispose
HCkMht instance = CkMht_Create(); // ... CkMht_Dispose(instance);
Creates an instance of the HCkMht object and returns a handle ("void *" pointer). The handle is passed in the 1st argument for the functions listed on this page.
Objects created by calling CkMht_Create must be freed by calling this method. A memory leak occurs if a handle is not disposed by calling this function. Also, any handle returned by a Chilkat "C" function must also be freed by the application by calling the appropriate Dispose method, such as CkMht_Dispose.
Callback Functions
Provides the opportunity for a method call to be aborted. If TRUE is returned, the operation in progress is aborted. Return FALSE to allow the current method call to continue. This callback function is called periodically based on the value of the HeartbeatMs property. (If HeartbeatMs is 0, then no callbacks are made.) As an example, to make 5 AbortCheck callbacks per second, set the HeartbeatMs property equal to 200.
See Also:C Example using Callback Functions
Provides the percentage completed for any method that involves network communications or time-consuming processing (assuming it is a method where a percentage completion can be measured). This callback is only called when it is possible to know a percentage completion, and when it makes sense to express the operation as a percentage completed. The pctDone argument will have a value from 1 to 100. For methods that complete very quickly, the number of PercentDone callbacks will vary, but the final callback should have a value of 100. For long running operations, no more than one callback per percentage point will occur (for example: 1, 2, 3, ... 98, 99, 100).
This callback counts as an AbortCheck callback, and takes the place of the AbortCheck event when it fires.
The return value indicates whether the method call should be aborted, or whether it should proceed. Return TRUE to abort, and FALSE to proceed.
This is a general callback that provides name/value information about what is happening at certain points during a method call. To see the information provided in ProgressInfo callbacks, if any, write code to handle this event and log the name/value pairs. Most are self-explanatory.
Called in the background thread when an asynchronous task completes. (Note: When an async method is running, all callbacks are in the background thread.)
Properties
AbortCurrent
void CkMht_putAbortCurrent(HCkMht cHandle, BOOL newVal);
When set to TRUE, causes the currently running method to abort. Methods that always finish quickly (i.e.have no length file operations or network communications) are not affected. If no method is running, then this property is automatically reset to FALSE when the next method is called. When the abort occurs, this property is reset to FALSE. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)
topBaseUrl
void CkMht_putBaseUrl(HCkMht cHandle, const char *newVal);
const char *CkMht_baseUrl(HCkMht cHandle);
When processing an HTML file or string (not a website URL), this defines the base URL to be used when converting relative HREFs to absolute HREFs.
topConnectTimeout
void CkMht_putConnectTimeout(HCkMht cHandle, int newVal);
The amount of time in seconds to wait before timing out when connecting to an HTTP server. The default value is 10 seconds.
topDebugHtmlAfter
void CkMht_putDebugHtmlAfter(HCkMht cHandle, const char *newVal);
const char *CkMht_debugHtmlAfter(HCkMht cHandle);
A filename to save the result HTML when converting a URL, file, or HTML string. If problems are experienced, the before/after HTML can be analyzed to help determine the cause.
topDebugHtmlBefore
void CkMht_putDebugHtmlBefore(HCkMht cHandle, const char *newVal);
const char *CkMht_debugHtmlBefore(HCkMht cHandle);
A filename to save the input HTML when converting a URL, file, or HTML string. If problems are experienced, the before/after HTML can be analyzed to help determine the cause.
topDebugLogFilePath
void CkMht_putDebugLogFilePath(HCkMht cHandle, const char *newVal);
const char *CkMht_debugLogFilePath(HCkMht cHandle);
If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.
This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:
- a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
- the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
- there is an internal problem (bug) in the Chilkat code that causes the hang.
DebugTagCleaning
void CkMht_putDebugTagCleaning(HCkMht cHandle, BOOL newVal);
When TRUE causes the Mht class to be much more verbose in its logging. The default is FALSE.
topEmbedImages
void CkMht_putEmbedImages(HCkMht cHandle, BOOL newVal);
Controls whether images are embedded in the MHT/EML, or whether the IMG SRC attributes are left as external URL references. If false, the IMG SRC tags are converted to absolute URLs (if necessary) and the images are not embedded within the MHT/EML.
topEmbedLocalOnly
void CkMht_putEmbedLocalOnly(HCkMht cHandle, BOOL newVal);
If TRUE, only images found on the local filesystem (i.e. links to files) will be embedded within the MHT.
topFetchFromCache
void CkMht_putFetchFromCache(HCkMht cHandle, BOOL newVal);
If TRUE, page parts such as images, style sheets, etc. will be fetched from the disk cache if possible. The disk cache root may be defined by calling AddCacheRoot. The default value is FALSE.
topHeartbeatMs
void CkMht_putHeartbeatMs(HCkMht cHandle, int newVal);
The time interval, in milliseconds, between AbortCheck event callbacks. The heartbeat/AbortCheck provides a means for an application to abort any MHT method before completion.
The default value is 0, which means that no AbortCheck events will be fired.
topIgnoreMustRevalidate
void CkMht_putIgnoreMustRevalidate(HCkMht cHandle, BOOL newVal);
Some HTTP responses contain a "Cache-Control: must-revalidate" header. If this is present, the server is requesting that the client always issue a revalidate HTTP request instead of serving the page directly from cache. If IgnoreMustRevalidate is set to TRUE, then Chilkat MHT will serve the page directly from cache without revalidating until the page is no longer fresh. (assuming that FetchFromCache is set to TRUE)
The default value of this property is FALSE.
topIgnoreNoCache
void CkMht_putIgnoreNoCache(HCkMht cHandle, BOOL newVal);
Some HTTP responses contain headers of various types that indicate that the page should not be cached. Chilkat MHT will adhere to this unless this property is set to TRUE.
The default value of this property is FALSE.
topLastErrorHtml
const char *CkMht_lastErrorHtml(HCkMht cHandle);
Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.
topLastErrorText
const char *CkMht_lastErrorText(HCkMht cHandle);
Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.
LastErrorXml
const char *CkMht_lastErrorXml(HCkMht cHandle);
Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.
topLastMethodSuccess
void CkMht_putLastMethodSuccess(HCkMht cHandle, BOOL newVal);
Indicate whether the last method call succeeded or failed. A value of TRUE indicates success, a value of FALSE indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:
- Any method that returns a string.
- Any method returning a Chilkat object, binary bytes, or a date/time.
- Any method returning a standard boolean status value where success = TRUE and failure = FALSE.
- Any method returning an integer where failure is defined by a return value less than zero.
Note: Methods that do not fit the above requirements will always set this property equal to TRUE. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.
topNoScripts
void CkMht_putNoScripts(HCkMht cHandle, BOOL newVal);
Only applies when creating MHT files. Scripts are always removed when creating EML or emails from HTML. If set to TRUE, then all scripts are removed, if set to FALSE (the default) then scripts are not removed.
topNtlmAuth
void CkMht_putNtlmAuth(HCkMht cHandle, BOOL newVal);
Setting this property to TRUE causes the MHT component to use NTLM authentication (also known as IWA -- or Integrated Windows Authentication) when authentication with an HTTP server.
The default value of this property is FALSE.
topNumCacheLevels
void CkMht_putNumCacheLevels(HCkMht cHandle, int newVal);
The number of directory levels to be used under each cache root. The default is 0, meaning that each cached item is stored in a cache root directory. A value of 1 causes each cached page to be stored in one of 255 subdirectories named "0","1", "2", ..."255" under a cache root. A value of 2 causes two levels of subdirectories ("0..255/0..255") under each cache root. The MHT control automatically creates subdirectories as needed. The reason for mutliple levels is to alleviate problems that may arise when huge numbers of files are stored in a single directory. For example, Windows Explorer does not behave well when trying to display the contents of directories with thousands of files.
topNumCacheRoots
The number of cache roots to be used for the disk cache. This allows the disk cache spread out over multiple disk drives. Each cache root is a string indicating the drive letter and directory path. For example, "E:\Cache". To create a cache with four roots, call AddCacheRoot once for each directory root.
topPreferIpv6
void CkMht_putPreferIpv6(HCkMht cHandle, BOOL newVal);
If TRUE, then use IPv6 over IPv4 when both are supported for a particular domain. The default value of this property is FALSE, which will choose IPv4 over IPv6.
topPreferMHTScripts
void CkMht_putPreferMHTScripts(HCkMht cHandle, BOOL newVal);
This property provides a means for the noscript option to be selected when possible. If PreferMHTScripts = FALSE, then scripts with noscript alternatives are removed and the noscript content is kept. If TRUE (the default), then scripts are preserved and the noscript options are discarded.
topProxy
void CkMht_putProxy(HCkMht cHandle, const char *newVal);
const char *CkMht_proxy(HCkMht cHandle);
(Optional) A proxy host:port if a proxy is necessary to access the Internet. The proxy string should be formatted as "hostname:port", such as "www.chilkatsoft.com:100".
topProxyLogin
void CkMht_putProxyLogin(HCkMht cHandle, const char *newVal);
const char *CkMht_proxyLogin(HCkMht cHandle);
If an HTTP proxy is used and it requires authentication, this property specifies the HTTP proxy login.
topProxyPassword
void CkMht_putProxyPassword(HCkMht cHandle, const char *newVal);
const char *CkMht_proxyPassword(HCkMht cHandle);
If an HTTP proxy is used and it requires authentication, this property specifies the HTTP proxy password.
topReadTimeout
void CkMht_putReadTimeout(HCkMht cHandle, int newVal);
The amount of time in seconds to wait before timing out when reading from an HTTP server. The ReadTimeout is the amount of time that needs to elapse while no additional data is forthcoming. During a long data transfer, if the data stream halts for more than this amount, it will timeout. Otherwise, there is no limit on the length of time for the entire data transfer.
The default value is 20 seconds.
topRequireSslCertVerify
void CkMht_putRequireSslCertVerify(HCkMht cHandle, BOOL newVal);
If TRUE, then the HTTP client will verify the server's SSL certificate. The certificate is expired, or if the cert's signature is invalid, the connection is not allowed. The default value of this property is FALSE.
topSocksHostname
void CkMht_putSocksHostname(HCkMht cHandle, const char *newVal);
const char *CkMht_socksHostname(HCkMht cHandle);
The SOCKS4/SOCKS5 hostname or IPv4 address (in dotted decimal notation). This property is only used if the SocksVersion property is set to 4 or 5).
topSocksPassword
void CkMht_putSocksPassword(HCkMht cHandle, const char *newVal);
const char *CkMht_socksPassword(HCkMht cHandle);
The SOCKS5 password (if required). The SOCKS4 protocol does not include the use of a password, so this does not apply to SOCKS4.
topSocksPort
void CkMht_putSocksPort(HCkMht cHandle, int newVal);
The SOCKS4/SOCKS5 proxy port. The default value is 1080. This property only applies if a SOCKS proxy is used (if the SocksVersion property is set to 4 or 5).
topSocksUsername
void CkMht_putSocksUsername(HCkMht cHandle, const char *newVal);
const char *CkMht_socksUsername(HCkMht cHandle);
The SOCKS4/SOCKS5 proxy username. This property is only used if the SocksVersion property is set to 4 or 5).
topSocksVersion
void CkMht_putSocksVersion(HCkMht cHandle, int newVal);
SocksVersion May be set to one of the following integer values:
0 - No SOCKS proxy is used. This is the default.
4 - Connect via a SOCKS4 proxy.
5 - Connect via a SOCKS5 proxy.
UnpackDirect
void CkMht_putUnpackDirect(HCkMht cHandle, BOOL newVal);
If TRUE, then the UnpackMHT and UnpackMHTString methods will unpack the MHT directly with no transformations. Normally, the related parts are unpacked to a "parts" sub-directory, and the unpacked HTML is edited to update references to point to the unpacked image and script files. When unpacking direct, the HTML is not edited, and the related parts are unpacked to sub-directories rooted in the directory where HTML file is created (i.e. the unpack directory). When unpacking direct, the "partsSubDir" argument of the UnpackMHT* methods is unused.
Note: It is only possible to directly unpack MHT files where the Content-Location headers DO NOT contain URLs. The MHT must be such that the Content-Location headers of the related items contain relative paths.
Note: The default value of this property is FALSE.
topUnpackUseRelPaths
void CkMht_putUnpackUseRelPaths(HCkMht cHandle, BOOL newVal);
Controls whether absolute or relative paths are used when referencing images in the unpacked HTML. The default value is TRUE indicating that relative paths will be used. To use absolute paths, set this property value equal to FALSE.
topUpdateCache
void CkMht_putUpdateCache(HCkMht cHandle, BOOL newVal);
Controls whether the cache is automatically updated with the responses from HTTP GET requests. If TRUE, the disk cache is updated, if FALSE (the default), the cache is not updated.
topUseCids
void CkMht_putUseCids(HCkMht cHandle, BOOL newVal);
Controls whether CID URLs are used for embedded references when generating MHT or EML documents. If UseCids is FALSE, then URLs are left unchanged and the embedded items will contain "content-location" headers that match the URLs in the HTML. If TRUE, CIDs are generated and the URLs within the HTML are replaced with "CID:" links.
The default value of this property is TRUE.
topUseFilename
void CkMht_putUseFilename(HCkMht cHandle, BOOL newVal);
If TRUE, a "filename" attribute is added to each Content-Disposition MIME header field for each embedded item (image, style sheet, etc.). If FALSE, then no filename attribute is added.
The default value of this property is TRUE.
topUseIEProxy
void CkMht_putUseIEProxy(HCkMht cHandle, BOOL newVal);
If TRUE, the proxy host/port used by Internet Explorer will also be used by Chilkat MHT.
topUseInline
void CkMht_putUseInline(HCkMht cHandle, BOOL newVal);
If TRUE, an "inline" attribute is added to each Content-Disposition MIME header field for each embedded item (image, style sheet, etc.). If FALSE, then no inline attribute is added.
The default value of this property is TRUE.
topUtf8
void CkMht_putUtf8(HCkMht cHandle, BOOL newVal);
When set to TRUE, all "const char *" arguments are interpreted as utf-8 strings. If set to FALSE (the default), then "const char *" arguments are interpreted as ANSI strings. Also, when set to TRUE, and Chilkat method returning a "const char *" is returning the utf-8 representation. If set to FALSE, all "const char *" return values are ANSI strings.
topVerboseLogging
void CkMht_putVerboseLogging(HCkMht cHandle, BOOL newVal);
If set to TRUE, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is FALSE. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
topVersion
WebSiteLogin
void CkMht_putWebSiteLogin(HCkMht cHandle, const char *newVal);
const char *CkMht_webSiteLogin(HCkMht cHandle);
(Optional) Specifies the login if a a Web page is accessed that requires a login
topWebSiteLoginDomain
void CkMht_putWebSiteLoginDomain(HCkMht cHandle, const char *newVal);
const char *CkMht_webSiteLoginDomain(HCkMht cHandle);
The optional domain name to be used with NTLM authentication.
topWebSitePassword
void CkMht_putWebSitePassword(HCkMht cHandle, const char *newVal);
const char *CkMht_webSitePassword(HCkMht cHandle);
Optional) Specifies the password if a a Web page is accessed that requires a login and password
topMethods
AddCacheRoot
If disk caching is used, this must be called once for each cache root. For example, if the cache is spread across D:\cacheRoot, E:\cacheRoot, and F:\cacheRoot, an application would setup the cache object by calling AddRoot three times -- once with "D:\cacheRoot", once with "E:\cacheRoot", and once with "F:\cacheRoot".
AddCustomHeader
Adds a custom HTTP header to all HTTP requests sent by the MHT component. To add multiple header fields, call this method once for each custom header.
topAddExternalStyleSheet
(This method rarely needs to be called.) Includes an additional style sheet that would not normally be included with the HTML. This method is provided for cases when style sheet names are constructed and dynamically included in Javascript such that MHT .NET cannot know beforehand what stylesheet to embed. MHT .NET by default downloads and embeds all stylesheets externally referenced by the HTML
topClearCustomHeaders
Removes all custom headers that may have accumulated from previous calls to AddCustomHeader.
topExcludeImagesMatching
(This method rarely needs to be called.) Tells Chilkat MHT .NET to not embed any images whose URL matches a pattern. Sometimes images can be referenced within style sheets and not actually used when rendering the page. In cases like those, the image will appear as an attachment in the HTML email. This feature allows you to explicitly remove those images from the email so no attachments appear.
topGetAndSaveEML
Creates an EML file from a web page or HTML file. All external images and style sheets are downloaded and embedded in the EML file.
Returns TRUE for success, FALSE for failure.
topGetAndSaveEMLAsync (1)
Creates an asynchronous task to call the GetAndSaveEML method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Returns NULL on failure
topGetAndSaveMHT
Creates an MHT file from a web page or local HTML file. All external images, scripts, and style sheets are downloaded and embedded in the MHT file.
Returns TRUE for success, FALSE for failure.
GetAndSaveMHTAsync (1)
Creates an asynchronous task to call the GetAndSaveMHT method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Returns NULL on failure
topGetAndZipEML
Creates an EML file from a web page or HTML file, compresses, and appends to a new or existing Zip file. All external images and style sheets are downloaded and embedded in the EML.
Returns TRUE for success, FALSE for failure.
topGetAndZipEMLAsync (1)
Creates an asynchronous task to call the GetAndZipEML method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Returns NULL on failure
topGetAndZipMHT
Creates an MHT file from a web page or HTML file, compresses, and appends to a new or existing Zip file. All external images and style sheets are downloaded and embedded in the MHT.
Returns TRUE for success, FALSE for failure.
topGetAndZipMHTAsync (1)
Creates an asynchronous task to call the GetAndZipMHT method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Returns NULL on failure
topGetCacheRoot
const char *CkMht_getCacheRoot(HCkMht cHandle, int index);
Returns the Nth cache root (indexing begins at 0). Cache roots are set by calling AddCacheRoot one or more times.
Returns TRUE for success, FALSE for failure.
topGetEML
const char *CkMht_getEML(HCkMht cHandle, const char *url_or_htmlFilepath);
Creates EML from a web page or HTML file, and returns the EML (MIME) message data as a string.
Returns TRUE for success, FALSE for failure.
topGetEMLAsync (1)
Creates an asynchronous task to call the GetEML method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Returns NULL on failure
topGetMHT
const char *CkMht_getMHT(HCkMht cHandle, const char *url_or_htmlFilepath);
Creates MHT from a web page or local HTML file, and returns the MHT (MIME) message data as a string
Returns TRUE for success, FALSE for failure.
topGetMHTAsync (1)
Creates an asynchronous task to call the GetMHT method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Returns NULL on failure
topHtmlToEML
const char *CkMht_htmlToEML(HCkMht cHandle, const char *htmlText);
Creates an in-memory EML string from an in-memory HTML string. All external images and style sheets are downloaded and embedded in the EML string that is returned.
Returns TRUE for success, FALSE for failure.
topHtmlToEMLAsync (1)
Creates an asynchronous task to call the HtmlToEML method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Returns NULL on failure
topHtmlToEMLFile
Creates an EML file from an in-memory HTML string. All external images and style sheets are downloaded and embedded in the EML file.
Returns TRUE for success, FALSE for failure.
topHtmlToEMLFileAsync (1)
Creates an asynchronous task to call the HtmlToEMLFile method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Returns NULL on failure
topHtmlToMHT
const char *CkMht_htmlToMHT(HCkMht cHandle, const char *htmlText);
Creates an in-memory MHT web archive from an in-memory HTML string. All external images and style sheets are downloaded and embedded in the MHT string.
Returns TRUE for success, FALSE for failure.
topHtmlToMHTAsync (1)
Creates an asynchronous task to call the HtmlToMHT method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Returns NULL on failure
topHtmlToMHTFile
Creates an MHT file from an in-memory HTML string. All external images and style sheets are downloaded and embedded in the MHT file.
Returns TRUE for success, FALSE for failure.
topHtmlToMHTFileAsync (1)
Creates an asynchronous task to call the HtmlToMHTFile method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Returns NULL on failure
topLoadTaskCaller
RemoveCustomHeader
Removes a custom header by header field name.
topRestoreDefaults
Restores the default property settings.
topUnpackMHT
Unpacks the contents of a MHT file. The destination directory is specified by unpackDir. The name of the HTML file created is specified by htmlFilename, and supporting files (images, javascripts, etc.) are created in partsSubDir, which is automatically created if it does not already exist.
Returns TRUE for success, FALSE for failure.
UnpackMHTString
Same as UnpackMHT, except the MHT is passed in as an in-memory string.
Returns TRUE for success, FALSE for failure.