TChilkatHashtable Delphi ActiveX Reference Documentation
TChilkatHashtable
Current Version: 9.5.0.98
Represents a collection of key/value pairs that are stored in a hash table.
Note: This class was added in Chilkat v9.5.0.51
Importing the Chilkat ActiveX into Delphi
Important: When upgrading to a new version of Chilkat, make sure to re-imported ActiveX DLL into Delphi to regenerate the files described below.
Two things are required to use an ActiveX in Delphi:
- The ActiveX DLL needs to be registered via regsvr32 on the system where the Delphi application runs. See How To Register ActiveX DLLs for detailed information.
- See also: ActiveX Registration Tutorial
- The ActiveX component needs to be "imported". Use the Delphi Import Component Wizard to import the Chilkat type library. This creates the following files: Chilkat_v9_5_0_TLB.pas and Chilkat_v9_5_0_TLB.dcr. The Chilkat_v9_5_0_TLB.pas should be added to your project.
To import the Chilkat type library, do the following:
- In the Delphi RAD Studio, select the menu item "Component" --> "Import a Type Library".
- Find "Chilkat ActiveX v9.5.0" in the list and select it. This will only appear in the list if the ChilkatAx-9.5.0-win32.dll (or ChilkatAx-9.5.0-x64.dll) has been registered w/ regsvr32.
- Check the "Generate Component Wrappers" checkbox.
- Select a directory where the unit files (.pas and .dcr) should be generated.
- Select "Create Unit" and then "Finish".
- Add the .pas to your Delphi project.
To use a Chilkat ActiveX object in your Delphi code, add "Chilkat_v9_5_0_TLB" to the "uses" statement. For example:
uses Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_v9_5_0_TLB;
Object Creation
var obj: TChilkatHashtable; ... begin obj := TChilkatHashtable.Create(Self); ... // When finished, free the object instance. obj.Free();
Properties
Count
The number of items (strings/integers) contained in the hash table.
topLastBinaryResult
The binary data returned by the last (binary data returning) method called. Only available if Chilkat.Global.KeepBinaryResult is set to 1. This provides a means for obtaining large varbinary results in the SQL Server environment (where limitations exist in getting large amounts of data returned by method calls, but where temp tables can be used for binary properties).
topLastMethodSuccess
Indicate whether the last method call succeeded or failed. A value of 1 indicates success, a value of 0 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 = 1 and failure = 0.
- 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 1. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.
topLastStringResult
The string return value of the last (string returning) method called. Only available if Chilkat.Global.KeepStringResult is set to 1. This provides a means for obtaining large string results in the SQL Server environment (where limitations exist in getting long strings returned by method calls, but where temp tables can be used for string properties).
LastStringResultLen
The length, in characters, of the string contained in the LastStringResult property.
topMethods
AddFromXmlSb
Adds to the hash table from XML previously created by calling ToXmlSb.
Returns 1 for success, 0 for failure.
AddInt
Adds or replaces an entry with the given key and integer value to the hash table. Returns 1 if a new hash entry was added or replaced. Returns 0 if an out-of-memory condition occurred.
Returns 1 for success, 0 for failure.
topAddQueryParams
Adds URL query parameters into the hashtable. The queryParams has the form: "field1=value1&field2=value2&field3=value3...". It is assumed that the values are URL encoded, and this method automatically URL decodes the values prior to inserting into the hashtable.
Returns 1 for success, 0 for failure.
AddStr
Adds or replaces an entry with the given key and string value to the hash table. Returns 1 if a new hash entry was added or replaced. Returns 0 if an out-of-memory condition occurred.
Returns 1 for success, 0 for failure.
topClear
Removes all elements from the Hashtable.
topClearWithNewCapacity
Removes all elements from the Hashtable and re-sizes with the specified capacity.
The capacity is the number of buckets in the hash table. In the case of a "hash collision", a single bucket stores multiple entries, which must be searched sequentially. One rule of thumb is to set the capacity to twice the number of expected items to be hashed. It's also preferable to set the capacity to a prime number. (The 1st 10,000 prime numbers are listed here: https://primes.utm.edu/lists/small/10000.txt )
The initial default capacity of the hash table is 521.
Returns 1 for success, 0 for failure.
topContains
Determines if a given key is contained within the hash table. Returns 1 if the key exists, otherwise returns 0.
topContainsIntKey
Determines if a given key is contained within the hash table. Returns 1 if the key exists, otherwise returns 0.
topGetKeys
Appends the complete set of hashtable key strings to strTable.
Returns 1 for success, 0 for failure.
LookupInt
Returns the integer value associated with the specified key. If the key is not in the hash table, the return value is 0.
topLookupStr
Returns the string value associated with the specified key.
Returns a zero-length WideString on failure
topRemove
Removes the entry with the specified key from the hash table. Returns 1 if the key existed and was removed. Returns 0 if the key did not already exist.
topToQueryString
Serializes the hash table to a query string such as key1=value1&key2=value2&key3=value3 where each value is URL encoded.
Returns a zero-length WideString on failure
ToXmlSb
Serializes the hash table to XML format. The XML is appended to sbXml.
Returns 1 for success, 0 for failure.