java使用在IF语句中声明的变量
我刚在大学上过java编程课程。我们被要求做一个项目。然而,我在这里面临着一个困境,我们将非常感谢您的帮助
if (opt == 1) {
System.out.println("Enter your name:");
name1 = keyboard.next();
name2 = keyboard.next();
System.out.println("Enter your ID:");
ID = keyboard.nextInt();
System.out.println("Enter semesters taken:");
semtaken = keyboard.nextInt();
int[] semcode = new int[semtaken];
int[] subjectTaken = new int[semtaken];
double[] GPA = new double[semtaken];
double finalGPA;
for (i = 0; i < semtaken; i++) {
System.out.println("Enter semester code for semester no " + (i + 1));
semcode[i] = keyboard.nextInt();
System.out.println("Enter subjects taken:");
subjectTaken[i] = keyboard.nextInt();
String[][] subject = new String[subjectTaken[i]][4];
int subjectsTakenNO = subjectTaken[i];
System.out.println("Enter your subject code, hours, letter");
for (j = 0; j < subjectTaken.length; j++) {
for (int k = 0; k < 3; k++) {
subject[j][k] = keyboard.next();
}
}
GPA[i] = getGPA(subject, subjectsTakenNO);
totalGPA += GPA[i];
finalGPA = totalGPA / semtaken;
System.out.println("Your GPA for this term is" + getGPA(subject, subjectsTakenNO));
}
opt1 = true;
} /* Here is the PROBLEM. I want to get I want to get semtaken and gpa but it shows an
error (Variable not found) */
else if (opt == 2 && opt1) {
summary(name1, name2, ID, GPA, totalGPA, semtaken, semcode);
所以基本上,我想使用totalGPA、Semtake、semcode和GPA,它们都在IF中。如何使用它们而不显示错误“未找到变量”?我无法在IF之前初始化数组,因为我不知道它的大小。用户输入大小,因此它必须位于IF中
# 1 楼答案
如果满足以下条件,则可以在外部对其进行定义:
# 2 楼答案
只需在
if
之前的if
外部声明(但不初始化)所需的变量。比如说# 3 楼答案
你不能分配它,但你可以引入它