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OdbcParameter.Value Property

  • Reference

Definition

Namespace:
System.Data.Odbc
Assembly:
System.Data.Odbc.dll
Assembly:
System.Data.dll
Package:
System.Data.Odbc v9.0.0
Source:
OdbcParameter.cs
Source:
OdbcParameter.cs
Source:
OdbcParameter.cs

Gets or sets the value of the parameter.

public:
 virtual property System::Object ^ Value { System::Object ^ get(); void set(System::Object ^ value); };
public:
 property System::Object ^ Value { System::Object ^ get(); void set(System::Object ^ value); };
public override object? Value { get; set; }
[System.ComponentModel.TypeConverter(typeof(System.ComponentModel.StringConverter))]
public object Value { get; set; }
[System.ComponentModel.TypeConverter(typeof(System.ComponentModel.StringConverter))]
public override object Value { get; set; }
member this.Value : obj with get, set
[<System.ComponentModel.TypeConverter(typeof(System.ComponentModel.StringConverter))>]
member this.Value : obj with get, set
Public Overrides Property Value As Object
Public Property Value As Object

Property Value

Object

An Object that is the value of the parameter. The default value is null.

Implements

Value
Attributes
TypeConverterAttribute

Examples

The following example creates an OdbcParameter and sets some of its properties.

Public Sub CreateOdbcParameter()  
    Dim parameter As New OdbcParameter("Description", OdbcType.VarChar, 88)  
    parameter.Value = "garden hose"  
End Sub   

public void CreateOdbcParameter()   
 {  
    OdbcParameter parameter = new OdbcParameter("Description", OdbcType.VarChar, 88);  
    parameter.Value = "garden hose";  
 }

Remarks

For input parameters, the value is bound to the OdbcCommand that is sent to the server. For output and return-value parameters, the value is set on completion of the OdbcCommand and after the OdbcDataReader is closed.

When you send a null parameter value to the server, the user must specify DBNull, not null. A null value in the system is an empty object that has no value. DBNull is used to represent null values. If the parameter is used to call a stored procedure with parameters that have default values, setting Value to null causes the default value to be used.

If the application specifies the database type, the bound value is converted to that type when the provider sends the data to the server. The provider tries to convert any type of value if it supports the IConvertible interface. Conversion errors may result if the specified type is not compatible with the value.

Both the DbType and OdbcType properties can be inferred by setting Value. If applicable, the size, precision, and scale is also inferred from Value when the parameterized statement is executed. However, inferred values are not exposed to the user.

The Value property is overwritten by the Update method.

Applies to

See also