TParam class

In unit DB

Parameter description class.

Declaration

pascal

TParam = class(TCollectionItem)

Inheritance

Descends from it: TSQLDBParam

Description

TParam is one item in a TParams collection. It describes the name ( Name), type ( ParamType) and value ( Value) of a parameter in a parameterized query or stored procedure. Under normal circumstances, it should never be necessary to create a TParam instance manually; the TDataset descendent that owns the parameters should have created all necessary TParam instances.

Properties

`AsBCD`	public	Get or set parameter value as BCD value.
`AsBlob`	public	Return parameter value as a blob.
`AsBoolean`	public	Get/Set parameter value as a boolean value.
`AsByte`	public	Get/Set parameter value as a 8-bit unsigned integer value.
`AsBytes`	public	Get or set parameter value as TBytes.
`AsCurrency`	public	Get/Set parameter value as a currency value.
`AsDate`	public	Get/Set parameter value as a date (TDateTime) value.
`AsDateTime`	public	Get/Set parameter value as a date/time (TDateTime) value.
`AsFloat`	public	Get/Set parameter value as a floating-point value.
`AsInteger`	public	Get/Set parameter value as an integer (32-bit) value.
`AsLargeInt`	public	Get/Set parameter value as a 64-bit integer value.
`AsLongWord`	public	Get/Set parameter value as a 32-bit unsigned integer value.
`AsMemo`	public	Get/Set parameter value as a memo (string) value.
`AsShortInt`	public
`AsSingle`	public
`AsSmallInt`	public	Get/Set parameter value as a smallint value.
`AsString`	public	Get/Set parameter value as a string value.
`AsAnsiString`	public	Parameter contents as an ANSI string.
`AsUTF8String`	public	Parameter contents as an UTF8 string.
`AsUnicodeString`	public	Parameter contents as a Unicode string.
`AsTime`	public	Get/Set parameter value as a time (TDateTime) value.
`AsWord`	public	Get/Set parameter value as a word value.
`AsFMTBCD`	public	Parameter value as a BCD value.
`Bound`	public	Is the parameter value bound (set to fixed value).
`Dataset`	public	Dataset to which this parameter belongs.
`IsNull`	public	Is the parameter empty.
`NativeStr`	public	No description available.
`Text`	public	Read or write the value of the parameter as a string.
`AsWideString`	public	Get/Set the value as a widestring.
`DataType`	published	Data type of the parameter.
`Name`	published	Name of the parameter.
`NumericScale`	published	Numeric scale.
`ParamType`	published	Type of parameter.
`Precision`	published	Precision of the BCD value.
`Size`	published	Size of the parameter.
`Value`	published	Value as a variant.

Methods

`AssignParam`	protected
`AssignTo`	protected	Generic assignment function.
`GetAsBoolean`	protected
`GetAsBytes`	protected
`GetAsCurrency`	protected
`GetAsDateTime`	protected
`GetAsFloat`	protected
`GetAsInteger`	protected
`GetAsLargeInt`	protected
`GetAsLongWord`	protected
`GetAsMemo`	protected
`GetAsSingle`	protected
`GetAsString`	protected
`GetAsAnsiString`	protected
`GetAsUnicodeString`	protected
`GetAsUTF8String`	protected
`GetAsWideString`	protected
`GetAsVariant`	protected
`GetAsFMTBCD`	protected
`GetDisplayName`	protected	Returns the of the collectionitem.
`GetIsNull`	protected
`IsEqual`	protected
`SetAsBCD`	protected
`SetAsBlob`	protected
`SetAsBoolean`	protected
`SetAsByte`	protected
`SetAsBytes`	protected
`SetAsCurrency`	protected
`SetAsDate`	protected
`SetAsDateTime`	protected
`SetAsFloat`	protected
`SetAsInteger`	protected
`SetAsLargeInt`	protected
`SetAsLongWord`	protected
`SetAsMemo`	protected
`SetAsShortInt`	protected
`SetAsSingle`	protected
`SetAsSmallInt`	protected
`SetAsString`	protected
`SetAsAnsiString`	protected
`SetAsUTF8String`	protected
`SetAsUnicodeString`	protected
`SetAsWideString`	protected
`SetAsTime`	protected
`SetAsVariant`	protected
`SetAsWord`	protected
`SetAsFMTBCD`	protected
`SetDataType`	protected
`SetText`	protected
`Create`	public	Create a new parameter value.
`Assign`	public	Assign one parameter instance to another.
`AssignField`	public	Copy value from field instance.
`AssignToField`	public	Assign parameter value to field.
`AssignFieldValue`	public	Assign field value to the parameter.
`AssignFromField`	public	Copy field type and value.
`Clear`	public	Clear the parameter value.
`GetData`	public	Get the parameter value from a memory buffer.
`GetDataSize`	public	Return the size of the data.
`LoadFromFile`	public	Load a parameter value from file.
`LoadFromStream`	public	Load a parameter value from stream.
`SetBlobData`	public	Set BLOB data.
`SetData`	public	Set the parameter value from a buffer.

Inherited

From TCollectionItem (11)

Changed Collection Destroy DisplayName GetNamePath GetOwner ID Index SetCollection SetDisplayName SetIndex

From TPersistent (4)

DefineProperties FPOAttachObserver FPODetachObserver FPONotifyObservers

From TObject (40)

AfterConstruction BeforeDestruction CheckDisposed ClassInfo ClassName ClassNameIs ClassParent ClassType CleanupInstance DefaultHandler DefaultHandlerStr Dispatch DispatchStr Disposed DisposeOf Equals FieldAddress Free FreeInstance GetDisposed GetHashCode GetInterface GetInterfaceByStr GetInterfaceEntry GetInterfaceEntryByStr GetInterfaceTable GetInterfaceWeak GetLastCastErrorInfo InheritsFrom InitInstance InstanceSize MethodAddress MethodName newinstance QualifiedClassName SafeCallException StringMessageTable SystemHasExtendedRTTI ToString UnitName

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