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SqlDataSourceView.ParameterPrefix Property

Definition

Gets the string that is used to prefix a parameter placeholder in a parameterized SQL query.

protected:
 virtual property System::String ^ ParameterPrefix { System::String ^ get(); };
protected virtual string ParameterPrefix { get; }
member this.ParameterPrefix : string
Protected Overridable ReadOnly Property ParameterPrefix As String

Property Value

The "@" string.

Remarks

SQL queries and commands can be parameterized, in that they contain placeholders for values that are bound to the query at run time. Depending on the ADO.NET provider that is set for the SqlDataSource control, which is identified by the ProviderName property, the parameters are evaluated by alias or by their ordering in the ParameterCollection object.

If the ProviderName is not set or is set to the System.Data.SqlClient, parameters are evaluated by alias and the ParameterPrefix property is used to add a parameter prefix to the Name property of each Parameter object in a ParameterCollection during a data retrieval or data manipulation operation. If the ProviderName property is set to the System.Data.OleDb or System.Data.Odbc, the parameters are evaluated by order and the ParameterPrefix and Name properties are ignored.

If you extend the SqlDataSourceView class, you can override the ParameterPrefix property to supply a prefix other than the "@" string, if required.

Applies to