XLANG-s 運算式

運算式是一串運算子和運算元。 本主題將描述 XLANG/s 支援各種運算式的語法。

基本運算式

下列程式碼示範基本運算式的語法：

primary-expression:  
     literal  
     enum-constant  
     variable-reference  
     invocation-expression  
     message-field-reference  
     message-property-reference  
     message-part-property-reference  
     correlation-property-reference  
     port-property-reference  
     service-property-reference  
     service-link-property-reference  
     message-part-reference  
     parenthesized-expression  
     object-reference  
     checked-expression  
     unchecked-expression  
     intrinsic-expression  
     xpath-expression  
     exists-expression  
enum-constant:  
     enum-type-name.enum-member  
enum-type-name:  
     type-name  
enum-member:  
     identifier  
parenthesized-expression:  
     (expression)  
checked-expression:  
     checked(expression)  
     checked(statement)  
unchecked-expression:  
     unchecked(expression)  
     unchecked(statement)  
unary-expression:  
     primary-expression  
     + unary-expression  
     - unary-expression  
     ! unary-expression  
     ~ unary-expression  
     cast-expression  
     property-reference exists  
cast-expression:  
     (type-name) unary-expression  
multiplicative-expression:  
     exists-expression  
     multiplicative-expression * unary-expression  
     multiplicative-expression / unary-expression  
     multiplicative-expression % unary-expression  
additive-expression:  
     multiplicative-expression  
     additive-expression + multiplicative-expression  
     additive-expression – multiplicative-expression  
shift-expression:  
     additive-expression  
     shift-expression << additive-expression  
     shift-expression >> additive-expression  
relational-expression:  
     shift-expression  
     relational-expression < shift-expression  
     relational-expression > shift-expression  
     relational-expression <= shift-expression  
     relational-expression >= shift-expression  
equality-expression:  
     relational-expression  
     equality-expression == relational-expression  
     equality-expression != relational-expression  
and-expression:  
     equality-expression  
     and-expression & equality-expression  
exclusive-or-expression:  
     and-expression  
     exclusive-or-expression ^ and-expression  
inclusive-or-expression:  
     exclusive-or-expression  
     inclusive-or-expression | exclusive-or-expression  
conditional-and-expression:  
     inclusive-or-expression  
     conditional-and-expression && inclusive-or-expression  
conditional-or-expression:  
     conditional-and-expression  
     conditional-or-expression || conditional-and-expression  
conditional-expression:  
     conditional-or-expression  
exists-expression:  
     property-reference exists  
     property-reference exists message-reference  
     property-reference exists message-part-reference  
xpath-expression:  
     xpath(message-part-reference, string-expression)  
     xpath(string-expression)  
intrinsic-expression:  
     succeeded(identifier)  
assignment-expression:  
     variable-assignment  
     object-assignment  
variable-assignment:  
     variable-reference = conditional-expression  
object-assignment:  
     object-reference = object-creation-expression  
     object-reference = conditional-expression  
     object-reference = invocation-expression  
object-creation-expression:  
     new class-name(method-argument-list) //method-argument-list is optional  
     new class-name[integer-expression]  
invocation-expression:  
     object-reference.method-name(method-argument-list) //method-argument-list is optional  

服務和方法引數

下列程式碼示範服務和方法引數的語法：

service-argument-list:  
     service-argument  
     service-argument-list, service-argument  
service-argument:  
     param-direction message-reference //param-direction is optional  
     param-direction variable-reference //param-direction is optional  
     param-direction object-name //param-direction is optional  
     correlation-reference  
     service-link-name  
     port-name  
     conditional-expression  
method-argument-list:  
     method-argument  
     method-argument-list, method-argument  
method-argument:  
     message-reference  
     param-direction variable-reference //param-direction is optional  
     param-direction object-name //param-direction is optional  
     conditional-expression  
     param-direction message-part-reference //param-direction is optional  
     param-direction message-field-reference //param-direction is optional  

最上層的運算式

下列程式碼示範最上層運算式的語法：

expression:  
     conditional-expression  
     assignment-expression  
     invocation-expression  
constant-expression:  
     conditional-expression  
boolean-expression:  
     conditional-expression  
integer-expression:  
     conditional-expression  
date-time-expression:  
     conditional-expression  
time-span--expression:  
     conditional-expression  
string-expression:  
     conditional-expression  

另請參閱

XLANG-s 資料類型
XLANG-s 陳述式
XLANG-s 變數和運算子
XLANG-s 保留字
XLANG-s 至 BPEL4WS 類型轉換