package assignment_3_1;
import java.util.Scanner;
public class Assignment_3_1 {
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
//create a scanner
Scanner input = new Scanner (System.in);
//obtain package weight 1
System.out.print("Enter the Package Weight (In Pounds): ");
int packageWeight1 = input.nextInt();
double WeightCalc1 = 5;
double WeightCalc2 = 15;
double WeightCalc3 = 34;
double WeightCalc4 = 45;
double WeightCalc5 = 60;
double WeightCalc6 = 60;
double priceA = 12;
double priceB = 14;
double priceC = 17;
double priceD = 21;
double priceE = 33;
double priceF = 105;
//if WeightCalc1 >= packageWeight1 the base charge is 12
if (WeightCalc1 >= packageWeight1)
{
System.out.println("The Base Charge is : " + priceA);
int basePrice = 12;
}
else
{
//if WeightCalc2 >= packageWeight1 the base charge is 14
if (WeightCalc2 >= packageWeight1)
{
System.out.println("The Base Charge is: " + priceB);
int basePrice = 14;
}
else
{
//if WeightCalc3 >= packageWeight1 the base charge is 17
if (WeightCalc3 >= packageWeight1)
{
System.out.println("The Base Charge is: " + priceC);
int basePrice = 17;
}
else
{
//if weightCalc4 >= packageWeight1 the base charge is 21
if (WeightCalc4 >= packageWeight1)
{
System.out.println("The base charge is: " + priceD);
int basePrice = 21;
}
else
{
//if weightCalc5 >= packageWeight1 the base charge is 33
if (WeightCalc5 >= packageWeight1)
{
System.out.println("The base charge is: " + priceE );
int basePrice = 33;
}
else
{
//if weightCalc6 < packageWeight1 the base charge is 105
if (WeightCalc6 < packageWeight1)
{
System.out.println("The base charge is: " + priceF);
int basePrice = 105;
}
else
{
System.out.println("Re-Run the Program");
}
}
}
}
}
}
//obtain zipCode
System.out.println("Enter your 5 Digit Zip Code: ");
int zipCode = input.nextInt();
double perc1 = 3999;
double perc2 = 5000;
double perc3 = 5999;
double perc4 = 7000;
//if perc1 < basePrice < perc2
if (perc1 < basePrice < perc2)
{
}
}
}
我在if语句中声明了一个int，当我开始在大if语句之后编写底部部分时我尝试使用basePrice在if语句中声明的int我尝试更改int的名称并使用double而不是int，没有什么可以确定我做错了什么。
答案 0 :(得分：1)
在java中，变量的范围是块的本地。块通常是{...}之间的代码。如果你需要在粗体旁边使用它，那么你应该在块之外声明它。有关详细信息，请参阅示例。
if(condition){
int i=10;
}
你不能在if之外使用我。
如果你愿意，你应该做点什么
int i =0;
if(condition)
{
i=10;
}
现在您可以在if。
之外使用它答案 1 :(得分：1)
问题是每个int basePrice都在它自己的范围内声明，并且不存在于该范围之外。你想用所有的双打声明int，如下所示：
double WeightCalc1 = 5;
double WeightCalc2 = 15;
double WeightCalc3 = 34;
double WeightCalc4 = 45;
double WeightCalc5 = 60;
double WeightCalc6 = 60;
double priceA = 12;
double priceB = 14;
double priceC = 17;
double priceD = 21;
double priceE = 33;
double priceF = 105;
// declare basePrice here
int basePrice;
然后没有这些块：
//if WeightCalc1 >= packageWeight1 the base charge is 12
// base price only exists within these brackes
if (WeightCalc1 >= packageWeight1)
{
// base price only exists within these brackes
System.out.println("The Base Charge is : " + priceA);
int basePrice = 12;
}
您改为：
//if WeightCalc1 >= packageWeight1 the base charge is 12
if (WeightCalc1 >= packageWeight1)
{
System.out.println("The Base Charge is : " + priceA);
basePrice = 12;
}
答案 2 :(得分：0)
变量的范围仅限于此。
如果条件允许，你无法访问它。
您可以将其声明为全局，以便在另一个中访问它。
<强>更新
int basePrice = 0; // declare
之后在其他if条件中赋值。
if (WeightCalc1 >= packageWeight1)
{
System.out.println("The Base Charge is : " + priceA);
// int basePrice = 12; //--not like this
basePrice = 12; // assign
}
答案 3 :(得分：0)
在开头声明int basePrice（例如使用packageWeight1），将其初始化为某个值（0？）然后将所有int basePrice = ...更改为basePrice = ...
if语句完成后，执行内部声明的任何值都将丢失。
答案 4 :(得分：0)
basePrice在if语句的范围内定义。将其移到声明范围之外
int basePrice = 12;
if (weightCalc1 >= packageWeight1) {
...
还有声明
if (perc1 < basePrice < perc2) {
不会编译。也许你的意思是
if (perc1 < basePrice && basePrice < perc2) {
答案 5 :(得分：0)
在if之外声明它，因为如果只是
，你将其范围限制在那个范围内package assignment_3_1;
import java.util.Scanner;
public class Assignment_3_1 {
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
//create a scanner
Scanner input = new Scanner (System.in);
//obtain package weight 1
System.out.print("Enter the Package Weight (In Pounds): ");
int packageWeight1 = input.nextInt();
double WeightCalc1 = 5;
double WeightCalc2 = 15;
double WeightCalc3 = 34;
double WeightCalc4 = 45;
double WeightCalc5 = 60;
double WeightCalc6 = 60;
double priceA = 12;
double priceB = 14;
double priceC = 17;
double priceD = 21;
double priceE = 33;
double priceF = 105;
int basePrice = 12; // declare it here and it will work
//if WeightCalc1 >= packageWeight1 the base charge is 12
if (WeightCalc1 >= packageWeight1)
{
System.out.println("The Base Charge is : " + priceA);
}
答案 6 :(得分：0)
代码与basePrice有问题。您在basePrice内宣布if＆amp; else你正在外面使用它。尝试在main方法中声明为全局变量，以便您可以从main中的任何位置进行访问。
public static void main(String[] args) {
//create a scanner
Scanner input = new Scanner (System.in);
int basePrice = 0;
// Your rest of code will be here ....
}
答案 7 :(得分：0)
basePrice必须在主
的开头声明以下是一些重构：
private static Integer checkWeight(int packageWeight, int weightCalc, int price)
{
if (weightCalc >= packageWeight)
{
System.out.println("The Base Charge is: " + price);
return price;
}
else
{
return null;
}
}
public static void main(String[] args)
{
//create a scanner
Scanner input = new Scanner (System.in);
//obtain package weight 1
System.out.print("Enter the Package Weight (In Pounds): ");
int packageWeight1 = input.nextInt();
int[] weightCalcs = {5, 15, 34, 45, 60, 60};
int[] prices = {12, 14, 17, 21, 33, 105};
Integer basePrice = null;
for (int i = 0; i < weightCalcs.length; i++)
{
if ((basePrice = checkWeight(packageWeight1, weightCalcs[i], prices[i])) != null)
{
// price found !
break;
}
}
if (basePrice != null)
{
//obtain zipCode
System.out.println("Enter your 5 Digit Zip Code: ");
int zipCode = input.nextInt();
double perc1 = 3999;
double perc2 = 5000;
double perc3 = 5999;
double perc4 = 7000;
// TODO using basePrice for the next intructions
}
else
{
System.out.println("Re-Run the Program");
}
}