Dns

If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.

Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.

Possible causes of hangs include:

• A timeout property set to 0, indicating an infinite timeout.
• A hang occurring within an event callback in the application code.
• An internal bug in the Chilkat code causing the hang.

The number of milliseconds between each AbortCheck event callback. The AbortCheck callback allows an application to abort any DNS operation prior to completion. If HeartbeatMs is 0 (the default), no AbortCheck event callbacks will fire.

Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

Indicates the success or failure of the most recent method call: true means success, false means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages.

The maxiumum number of milliseconds to wait for the answer to a DNS query. A value of 0 is to wait indefinitely (no timeout). It's not a good idea to specify 0 (infinite timeout) or a value less than 1000 (1 second). The default value is 10000 milliseconds.

The number of nameservers currently being used by Chilkat for DNS queries in all objects/classes, such as for HTTP, Email, FTP, SSH, etc.

Specifies the TLS preference. Possible values are:

• 0 = No TLS
• 1 = Prefer TLS if possible.
• 2 = Require TLS

The default value is 0. If TLS is preferred then DNS nameservers with TLS capability will be tried first. If none succeed, then UDP/TCP will be tried. If TLS is required, then only TLS capable nameservers will be tried and all DNS queries will use TLS.

Note: To use TLS, your application needs to first specify nameservers by calling AddNameserver once per nameserver with the supportsTls argument set to true.

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.

Version of the component/library, such as "10.1.0"

Adds the default (auto-assigned) nameservers to the collection of nameservers used by Chilkat for DNS queries and domain to IP address lookups.

Adds a new nameserver to the collection of nameservers used by Chilkat for DNS queries and domain to IP address lookups. The ipAddr specifies the IPv4 address of the nameserver. The supportsTls indicates if the namserver supports DoT (DNS over TLS. DoT uses port 853 for encrypted DNS communication.) If the TlsPreference property is set to 1 or 2, then Chilkat will use TLS nameservers.

Returns the IP address of the Nth nameserver currently used by Chilkat for DNS queries and domain to IP address lookups. The index specifies the index of the nameserver. The 1st nameserver is at index 0.

Returns null on failure

Performs an DNS query for domain and returns the answer in answer. The type of DNS query is specified in recordType and can be A, AAAA, ALIAS, CAA, MX, NS, SOA, TXT. Additional record types can be added as needed.

Creates an asynchronous task to call the Query method with the arguments provided.

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns null on failure

Removes all nameservers from the collection of nameservers used by Chilkat. An application can call this method to reset to 0 nameservers before adding new nameservers. If a DNS domain to IP address resolution is needed by Chilkat, then the auto-assigned nameserver IP addresses will be automaticaly restored.

Removes a nameserver from the collection of nameservers used by Chilkat. The ipAddr is the IPv4 address of the nameserver to be removed.

Provides the opportunity for a method call to be aborted. The AbortCheck event is fired periodically based on the value of the HeartbeatMs property. If HeartbeatMs is 0, then no AbortCheck events will fire. As an example, to fire 5 AbortCheck events per second, set the HeartbeatMs property equal to 200.

Chilkat .NET Framework Event Implementation

Args are passed using Chilkat.AbortCheckEventArgs

Event callback implementation:

private void dns_OnAbortCheck(object sender, Chilkat.AbortCheckEventArgs args)
	{
	    // application code goes here.
	}

To add an event handler:

Chilkat.Dns dns = new Chilkat.Dns();
dns.OnAbortCheck += dns_OnAbortCheck;

Chilkat .NET Core Event Implementation

Event callback implementation:

public void handleAbortCheck(out bool abort)
	{
	    // application code goes here.
	}

To add an event handler:

Chilkat.Dns dns = new Chilkat.Dns();
// ...
Chilkat.Dns.AbortCheck abortCheck = new Chilkat.Dns.AbortCheck(handleAbortCheck);
dns.setAbortCheckCb(abortCheck);

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 event is only fired 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 operations (Chilkat method calls) 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).

The PercentDone callback counts as an AbortCheck event. For method calls that complete quickly such that PercentDone events fire, it may be that AbortCheck events don't fire because the opportunity to abort is already provided in the PercentDone callback. For time consuming operations, where the amount of time between PercentDone callbacks are long, AbortCheck callbacks may be used to allow for the operation to be aborted in a more responsive manner.

The abort output argument provides a means for aborting the operation. Setting it to true will cause the method to abort and return a failed status (or whatever return value indicates failure).

Chilkat .NET Framework Event Implementation

Args are passed using Chilkat.PercentDoneEventArgs

Event callback implementation:

private void dns_OnPercentDone(object sender, Chilkat.PercentDoneEventArgs args)
	{
	    // application code goes here.
	}

To add an event handler:

Chilkat.Dns dns = new Chilkat.Dns();
dns.OnPercentDone += dns_OnPercentDone;

Chilkat .NET Core Event Implementation

Event callback implementation:

public void handlePercentDone(int pctDone, out bool abort)
	{
	    // application code goes here.
	}

To add an event handler:

Chilkat.Dns dns = new Chilkat.Dns();
// ...
Chilkat.Dns.PercentDone percentDone = new Chilkat.Dns.PercentDone(handlePercentDone);
dns.setPercentDoneCb(percentDone);

A general name/value event that provides information about what is happening during a method call. To find out what information is available, write code to handle this event and log the name/value pairs. Most are self-explanatory.

Chilkat .NET Framework Event Implementation

Args are passed using Chilkat.ProgressInfoEventArgs

Event callback implementation:

private void dns_OnProgressInfo(object sender, Chilkat.ProgressInfoEventArgs args)
	{
	    // application code goes here.
	}

To add an event handler:

Chilkat.Dns dns = new Chilkat.Dns();
dns.OnProgressInfo += dns_OnProgressInfo;

Chilkat .NET Core Event Implementation

Event callback implementation:

public void handleProgressInfo(string name, string value)
	{
	    // application code goes here.
	}

To add an event handler:

Chilkat.Dns dns = new Chilkat.Dns();
// ...
Chilkat.Dns.ProgressInfo progressInfo = new Chilkat.Dns.ProgressInfo(handleProgressInfo);
dns.setProgressInfoCb(progressInfo);

Called in the background thread when an asynchronous task completes.

Chilkat .NET Framework Event Implementation

Args are passed using Chilkat.TaskCompletedEventArgs

Event callback implementation:

private void dns_OnTaskCompleted(object sender, Chilkat.TaskCompletedEventArgs args)
	{
	    // application code goes here.
	}

To add an event handler:

Chilkat.Dns dns = new Chilkat.Dns();
dns.OnTaskCompleted += dns_OnTaskCompleted;

Chilkat .NET Core Event Implementation

Event callback implementation:

public void handleTaskIdCompleted(int taskId)
	{
	    // application code goes here.
	}

To add an event handler:

Chilkat.Dns dns = new Chilkat.Dns();
// ...
Chilkat.Dns.TaskIdCompleted taskIdCompleted = new Chilkat.Dns.TaskIdCompleted(handleTaskIdCompleted);
dns.setTaskIdCompletedCb(taskIdCompleted);