Expression Class Reference

Represents expression parser and evaluator. More...

Collaboration diagram for Expression:

Public Member Functions
bool	Calculate (out object result)
	Calculates the expression. More...
bool	CalculateForTableRow (int RowIndex, int targetFieldIndex)
	Calculates the expression for the given table row and writes the result to the specified field. More...
bool	CalculateForTableRow2 (int RowIndex, out object result)
	Calculates the expression for the given table row. More...
Function	get_SupportedFunction (int functionIndex)
	Gets the specified function from the list of function recognized by the expression parser. More...
bool	Parse (string expr)
	Parses the specifies string and build an expression out of it. More...
bool	ParseForTable (string expr, Table tbl)
	Parses expression seeking for fields in the specified table. More...

Properties
string	LastErrorMessage [get]
	Gets the last error message. More...
int	LastErrorPosition [get]
	Gets the position of the last error. More...
int	NumSupportedFunctions [get]
	Gets the number of functions recognized by the expression parser. More...
Table	Table [get]
	Gets the table associated with the current expression. More...

Detailed Description

Represents expression parser and evaluator.

New API 4.9.4:

Added in version 4.9.4

Member Function Documentation

Calculate()

bool Expression.Calculate

(

out object

result

)

Calculates the expression.

Parameters

result

The result.

Returns

Result which is of string, double, or boolean type.

CalculateForTableRow()

bool Expression.CalculateForTableRow	(	int	RowIndex,
		int	targetFieldIndex
	)

Calculates the expression for the given table row and writes the result to the specified field.

Parameters

RowIndex	Index of the row.
targetFieldIndex	Index of the target field.

Returns

True on success.

CalculateForTableRow2()

bool Expression.CalculateForTableRow2	(	int	RowIndex,
		out object	result
	)

Calculates the expression for the given table row.

Parameters

RowIndex	Index of the row.
result	The result of calculation (string, double, or boolean).

Returns

True on success.

get_SupportedFunction()

Function Expression.get_SupportedFunction

(

int

functionIndex

)

Gets the specified function from the list of function recognized by the expression parser.

Parameters

functionIndex

Index of the function.

Returns

The function object with metadata.

Parse()

bool Expression.Parse

(

string

expr

)

Parses the specifies string and build an expression out of it.

Parameters

expr	The string with expression.

Returns

True on success.

ParseForTable()

bool Expression.ParseForTable	(	string	expr,
		Table	tbl
	)

Parses expression seeking for fields in the specified table.

Parameters

expr	The expression to parse.
tbl	The table.

Returns

True on success.

Property Documentation

LastErrorMessage

string Expression.LastErrorMessage

get

Gets the last error message.

LastErrorPosition

int Expression.LastErrorPosition

get

Gets the position of the last error.

NumSupportedFunctions

int Expression.NumSupportedFunctions

get

Gets the number of functions recognized by the expression parser.

Table

Table Expression.Table

get

Gets the table associated with the current expression.