它始終是合法的,在D程式設計巢狀if-else語句,這意味著你可以使用一個if或else if語句在另一個if或else if語句。
巢狀的if語句的語法如下:
if( boolean_expression 1) { /* Executes when the boolean expression 1 is true */ if(boolean_expression 2) { /* Executes when the boolean expression 2 is true */ } }
可以巢狀else if...else 以類似的方式,如巢狀的if語句。
import std.stdio; int main () { /* local variable definition */ int a = 100; int b = 200; /* check the boolean condition */ if( a == 100 ) { /* if condition is true then check the following */ if( b == 200 ) { /* if condition is true then print the following */ writefln("Value of a is 100 and b is 200" ); } } writefln("Exact value of a is : %d", a ); writefln("Exact value of b is : %d", b ); return 0; }
當上面的程式碼被編譯並執行,它會產生以下結果:
Value of a is 100 and b is 200 Exact value of a is : 100 Exact value of b is : 200