Question

我正在尝试从函数返回一个值，但它返回的值是值1.

假设在computeCivIndex()中有5个参数，即使我对值进行了硬编码，我收到的输出仍然是1.

为什么会这样？

float LocationData::computeCivIndex()
{
     civNum1 = 45.0 / 100;
     civNum2 = 20 + 50;
     civNum3 = civNum2 / 200;
     civNum4 = civNum1 - civNum3;
     civNum5 = 5 + 10;


    return civNum;
}

//display data
void LocationData::displaydata()
{
cout << "CIV value: " << computeCivIndex << endl;
}

Answer 1

您遗漏()中的cout << "CIV value: " << computeCivIndex() << endl;。对于大括号的重要性，您可以查看this link。

Answer 2

cout＆lt;＆lt; “CIV值：”＆lt;＆lt; computeCivIndex ＆lt;＆lt; ENDL;

似乎是打印函数的值（不是返回值）。您需要将函数括号放在：

中

cout＆lt;＆lt; “CIV值：”＆lt;＆lt; computeCivIndex（）＆lt;＆lt; ENDL;

Answer 3

//convert sunType to sunTypePercentage
float LocationData::computeCivIndex(string st, int earth, int moons, float particle, float plasma)
{

    float sunTypePercent;

    if(st == "Type 0")
    {
        sunTypePercent = 80.0;
    }
    else if(st == "Type B")
    {
        sunTypePercent = 45.0;
    }
    else if(st == "Type A")
    {
        sunTypePercent = 60.0;
    }
    else if(st == "Type F")
    {
        sunTypePercent = 75.0;
    }
    else if(st == "Type G")
    {
        sunTypePercent = 90.0;
    }
    else if(st == "Type K")
    {
        sunTypePercent = 80.0;
    }
    else if(st == "Type M")
    {
        sunTypePercent = 70.0;
    }

    // calculate CIV Value
    float civNum,civNum1,civNum2,civNum3,civNum4,civNum5;

    civNum1 = sunTypePercent / 100;
    civNum2 = plasma + particle;
    civNum3 = civNum2 / 200;
    civNum4 = civNum1 - civNum3;
    civNum5 = earth + moons;

    civNum = civNum4 * civNum5;


    return civNum;
}

//display data
void LocationData::displaydata()
{

    cout << "suntype: " << sunType << endl;
    cout << "earth: " << noOfEarthLikePlanets << endl;
    cout << "moons: " << noOfEarthLikeMoons << endl;
    cout << "particle: " << aveParticulateDensity << endl;
    cout <<"density: " << avePlasmaDensity << endl;
    cout << "CIV value: " << computeCivIndex()<< endl;
}

这是我遇到问题的实际代码。对于computeCivIndex（）函数，它实际上是我的LocationData.h文件中的公共LocationData类下的静态，看起来像这样。

static float compute CivIndex（string st，int earth，int moons，float particle，float plasma）;

所以为了从函数中检索值，我应该这样做吗？

cout＆lt;＆lt; “CIV值：”＆lt;＆lt; LocationData.computeCivIndex（）＆lt;＆lt; ENDL;

C ++从函数返回值

3 个答案: