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.NET Framework Class Library
TemplateControl..::.Eval Method (String, String)

Evaluates a data-binding expression using the specified format string to display the result.

Namespace: System.Web.UI
Assembly: System.Web (in System.Web.dll)
Syntax
Protected Friend Function Eval ( _
	expression As String, _
	format As String _
) As String
protected internal string Eval(
	string expression,
	string format
)
protected public:
String^ Eval(
	String^ expression, 
	String^ format
)
member Eval : 
        expression:string * 
        format:string -> string 

Parameters

expression
Type: System..::.String
The navigation path from the container to the public property value to place in the bound control property.
format
Type: System..::.String
A .NET Framework format string to apply to the result.

Return Value

Type: System..::.String
A string that results from the evaluation of the data-binding expression and conversion to a string type.
Exceptions
ExceptionCondition
InvalidOperationException

The data-binding method can only be used for controls contained on a Page.

ArgumentNullException

expression is nullNothingnullptra null reference (Nothing in Visual Basic).

- or -

expression is an empty string ("").

Remarks

The value of expression must evaluate to a public property.

The Eval method calls the Eval method using the GetDataItem method to resolve the object reference that the expression is evaluated against.

Version Information

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0
Platforms

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.