压缩代码：对一对元素的相同操作

Question

对于这种情况，有没有办法让代码更紧凑？

// pseudocode
if (A == 1) {
    if (B == 2) {
        action1;
    }
    if (B == 3) {
        action2;
    }
}

if (B == 1) {
    if (A == 2) {
        action1;
    }
    if (A == 3) {
        action2;
    }
}

在Objective-C / Objective-C ++中？

又一个例子：

if (((int)fixtureUserDataA == FIXTURE_FOOT_SENSOR || ((int)fixtureUserDataB == FIXTURE_FOOT_SENSOR ))) {

    // Hero foot sensors
    if (bodyA->GetUserData() != NULL) {
        CCSprite * sprite = (CCSprite*)bodyA->GetUserData();
        if (sprite.tag == TAG_HERO) {
            [Hero sharedInstance].numFootContacts++;             
        }
    }

    if (bodyB->GetUserData() != NULL) {
        CCSprite * sprite = (CCSprite*)bodyB->GetUserData();
        if (sprite.tag == TAG_HERO) {
            [Hero sharedInstance].numFootContacts++;             
        }
    }
}

是否可以只使用一种或多种透明结构？

Answer 1

代表第二个例子：

checkBody(bodyA);
checkBody(bodyB);

void checkBody(Body* body)
{
    CCSprite * sprite = (CCSprite*)body->GetUserData();
        if (sprite.tag == TAG_HERO) {
            [Hero sharedInstance].numFootContacts++;             
        }
}

Answer 2

if (A == 1 || B == 1)
    if (A + B == 3)
        action1;
    else if (A + B == 4)
        action2;