>Hi,
>
>Could someone suggest why I am having a problem (actually not me but the customer) in the following segment of code:
>
>The container with the text box has a property control_source. This property has a value V_WORK.EMPLOYEE
>
>The code then checks is the value of the field EMPLOYEE in the cursor V_WORK has been change. Here is the code:
>
>

>		cControlSource = ALLTRIM( this.control_source )
>		IF EVALUATE( cControlSource ) == OLDVAL( cControlSource )		
>			RETURN .T.
>		ENDIF 
>

>
>The problem occurs on the line above, EVALUATE( cControlSource ) == OLDVAL( cControlSource ), and it does
>ALIAS IS NOT FOUND. I verified that the entry in .control_source exists as described above.
>
>TIA.
>
>UPDATE. the following code checks that the alias V_WORK exist and is open. This code, below, is before the code above (just in case someone wonders if the alias is indeed exists and open
>

>
>IF !EMPTY( this.control_source )
>	cAlias = SUBSTR( ALLTRIM(this.control_source), 1, AT('.',ALLTRIM(this.control_source)) - 1)
>	IF SELECT( cAlias ) > 0
>		cControlSource = ALLTRIM( this.control_source )
>		IF EVALUATE( cControlSource ) == OLDVAL( cControlSource )		
>			RETURN .T.
>		ENDIF 
>      ENDIF
>ENDIF
>

Hrm... Within the context in which the code you supply is running under, what does "THIS" refer to? Is it the textbox or the container in which the textbox resides?
You state that "control_source" is a property of a container that refers to an alias.
What is the "ControlSource" value of the textbox? Does it agree with the "Control_Source" value of the container?