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DataParameter Class

Definition

Represents a data parameter that is derived from a data source command, or that is passed with a command to a data source.

public ref class DataParameter abstract
public abstract class DataParameter
type DataParameter = class
Public MustInherit Class DataParameter
Inheritance
DataParameter
Derived

Constructors

DataParameter()

Class constructor. Initializes a nonparameterized instance of the DataParameter class.

DataParameter(Boolean)

Class constructor. Initializes a parameterized instance of the DataParameter class, along with an indication whether the instance was derived using the DeriveParameters(String, Int32, Int32) method.

Properties

DefaultPrecision

Retrieves a byte value specifying the default precision for the current parameter type.

DefaultScale

Retrieves a byte value specifying the default scale for the current parameter type.

DefaultSize

Retrieves and integer value specifying the default size for the current parameter type.

Direction

Retrieves or sets a DataParameterDirection object specifying the direction of the parameter.

IsDerived

Retrieves a Boolean value that indicates whether this parameter was derived from the data source.

IsFixedPrecision

Retrieves a Boolean value indicating whether the precision for the current parameter type is fixed.

IsFixedScale

Retrieves a Boolean value indicating whether the scale for the current parameter type is fixed.

IsFixedSize

Retrieves a Boolean value indicating whether the size for the current parameter type is fixed.

IsNullable

Retrieves a Boolean value indicating whether this parameter can have a null value.

IsOptional

Retrieves a Boolean value indicating whether this parameter is optional, in cases where this parameter is a derived parameter.

Name

Retrieves or sets the string literal name of the parameter.

Precision

Retrieves or sets a byte value specifying the precision of the parameter.

Scale

Retrieves or sets a byte value specifying the scale of the parameter.

Size

Retrieves or sets an integer value specifying the size of the parameter.

Type

Retrieves or sets the data-source-specific type of the parameter.

Value

Retrieves or sets the value of the parameter.

Methods

GetDirectionImpl()

Retrieves the parameter direction.

GetIsNullableImpl()

Retrieves a Boolean value indicating whether or not this parameter can be null.

GetIsOptionalImpl()

Retrieves a Boolean value indicating whether this parameter is optional.

GetNameImpl()

Retrieves the name of the parameter.

GetPrecisionImpl()

Retrieves a byte value specifying the precision of the parameter.

GetScaleImpl()

Retrieves a byte value specifying the scale of the parameter.

GetSizeImpl()

Retrieves an integer value specifying the size of the parameter.

GetTypeFrom(Object)

Infers the data-source-specific parameter type from a parameter value.

GetTypeImpl()

Retrieves the data-source-specific type of the parameter.

GetValueImpl()

Retrieves the value of a specified parameter.

IsSupportedDirection(DataParameterDirection)

Retrieves a Boolean value indicating whether the specified parameter direction is supported.

IsValidType(String)

Retrieves a Boolean value indicating whether the specified data-source-specific type is a valid type.

OnDirectionChanged()

Called when the Direction property is changed to signal a change in the parameter direction.

OnDirectionChanging(DataParameterDirection)

Called when the Direction property is about to change.

OnNameChanged()

Called when the Name property has changed.

OnNameChanging(String)

Called when the Name property is about to change.

OnPrecisionChanged()

Called when the Precision property has changed.

OnPrecisionChanging(Byte)

Called when the Precision property is about to change.

OnScaleChanged()

Called when the Scale property has changed.

OnScaleChanging(Byte)

Called when the Scale property is about to change.

OnSizeChanged()

Called when the Size property has changed.

OnSizeChanging(Int32)

Called when the Size property is about to change.

OnTypeChanged()

Called when the Type property has changed.

OnTypeChanging(String)

Called when the Type property is about to change.

OnValueChanged()

Called when the Value property has changed.

OnValueChanging(Object)

Called when the Value property is about to change.

Parse(String)

Disassembles a parameter value in a string format and converts the value to the correct type.

SetDirectionImpl(DataParameterDirection)

Sets the direction of the parameter using the DataParameterDirection enumeration.

SetNameImpl(String)

Sets the name of the parameter.

SetPrecisionImpl(Byte)

Sets a byte value specifying the precision of the parameter.

SetScaleImpl(Byte)

Sets a byte value specifying the scale of the parameter.

SetSizeImpl(Int32)

Sets an integer value specifying the size of this parameter.

SetTypeImpl(String)

Sets the data type of this parameter.

SetValueImpl(Object)

Sets the value of this parameter.

ToString()

Retrieves a string representation of the value of this parameter.

TryConvertValue(Object, String)

Attempts to convert the specified value to the specified type.

Applies to