property FormatConditionalAppearance.Expression as String
Specifies the conditional expression that determines whether the current format is applied on the pivot's data.

 TypeDescription 
   String A String expression that defines the conditional-expression that needs to match the value, so the current format is applied to the cell. For instance, "len(value) = 0" indicates any empty value.  
The Expression property defines the conditional expression that determines whether the current format is applied on the pivot's value. The Expression parameter of the Add method, is equivalent with the Expression property. When the current format is applied to a column, the Expression is evaluated ( value keyword in the Expression indicates the value in the column ), and if it is True, the current format is applied to the cell, else it is not. The ContextEditExpression property indicates whether the item of the current conditional-format object in the control's content menu displays/edits the conditional expression, at runtime. The FormatConditionalAppearance format is not applied to any value, if the expression is not valid ( empty or syntactically incorrect ).

For instance: 

The value keyword in the Expression property indicates the value/result to be evaluated.

The supported binary arithmetic operators are:

The supported unary boolean operators are:

The supported binary boolean operators are:

The supported binary boolean operators, all these with the same priority 0, are :

The supported ternary operators, all these with the same priority 0, are :

"expression ? true_part : false_part"

, while it executes and returns the true_part if the expression is true, else it executes and returns the false_part. For instance, the "%0 = 1 ? 'One' : (%0 = 2 ? 'Two' : 'not found')" returns 'One' if the value is 1, 'Two' if the value is 2, and 'not found' for any other value. A n-ary equivalent operation is the case() statement, which is available in newer versions of the component.

The supported n-ary operators are (with priority 5):

"expression in (c1,c2,c3,...cn)"

, where the c1, c2, ... are constant elements. The constant elements could be numeric, date or string expressions. For instance the "value in (11,22,33,44,13)" is equivalent with "(expression = 11) or (expression = 22) or (expression = 33) or (expression = 44) or (expression = 13)". The in operator is not a time consuming as the equivalent or version is, so when you have large number of constant elements it is recommended using the in operator. Shortly, if the collection of elements has 1000 elements the in operator could take up to 8 operations in order to find if an element fits the set, else if the or statement is used, it could take up to 1000 operations to check, so by far, the in operator could save time on finding elements within a collection.

"expression switch (default,c1,c2,c3,...,cn)"

, where the c1, c2, ... are constant elements, and the default is a constant element being returned when the element is not found in the collection. The constant elements could be numeric, date or string expressions.  The equivalent syntax is "%0 = c 1 ? c 1 : ( %0 = c 2 ? c 2 : ( ... ? . : default) )". The switch operator is very similar with the in operator excepts that the first element in the switch is always returned by the statement if the element is not found,  while the returned value is the value itself instead -1. For instance, the "%0 switch ('not found',1,4,7,9,11)" gets 1, 4, 7, 9 or 11, or 'not found' for any other value. As the in operator the switch operator uses binary searches for fitting the element, so it is quicker that iif (immediate if operator) alterative.

"expression case ([default : default_expression ; ] c1 : expression1 ; c2 : expression2 ; c3 : expression3 ;....)"

If the default part is missing, the case() operator returns the value of the expression if it is not found in the collection of cases ( c1, c2, ...). For instance, if the value of expression is not any of c1, c2, .... the default_expression is executed and returned. If the value of the expression is c1, then the case() operator executes and returns the expression1. The default, c1, c2, c3, ... must be constant elements as numbers, dates or strings. For instance, the "date(shortdate(value)) case (default:0 ; #1/1/2002#:1 ; #2/1/2002#:1; #4/1/2002#:1; #5/1/2002#:1)" indicates that only #1/1/2002#, #2/1/2002#,  #4/1/2002# and  #5/1/2002# dates returns 1, since the others returns 0. For instance the following sample specifies the hour being non-working for specified dates: "date(shortdate(value)) case(default:0;#4/1/2009# : hour(value) >= 6 and hour(value) <= 12 ; #4/5/2009# : hour(value) >= 7 and hour(value) <= 10 or hour(value) in(15,16,18,22); #5/1/2009# : hour(value) <= 8)" statement indicates the working hours for dates as follows:

The in, switch and case() use binary search to look for elements so they are faster then using iif and or expressions.

Obviously, the priority of the operations inside the expression is determined by ( ) parenthesis and the priority for each operator. 

The supported conversion unary operators are:

Other known operators for numbers are:

Other known operators for strings are:

Other known operators for dates are:

 


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