处理异常

1private fun calculate(): Int {
2    return 1 / 0
3}
4
5private fun printCalculated() {
6    println(calculate())
7}
8
9fun main() {
10    println("Before")
11    printCalculated()
12    println("After")
13}

1fun main() {
2    val i1 = "10".toInt()
3    println(i1)
4    val i2 = "ABC".toInt()
5    println(i2)
6}

1private fun functionThrowing() {
2    throw ArithmeticException("Some message")
3}
4
5fun main() {
6    println("Before")
7    functionThrowing()
8    println("After")
9}

1class MyException : Throwable("Some message")
2object MyExceptionObject : Throwable("Some message")
3
4private fun functionThrowing() {
5    throw MyException()
6    // 或者 throw MyExceptionObject
7}
8
9fun main() {
10    println("Before")
11    functionThrowing()
12    println("After")
13}

1class MyException : Throwable("Some message")
2
3fun someFunction() {
4    throw MyException()
5    println("不会被打印")
6}
7
8fun main() {
9    try {
10        someFunction()
11        println("不会被打印")
12    } catch (e: MyException) {
13        println("捕获到 $e")
14        // 捕获到 MyException: Some message
15    }
16}

1import java.lang.NumberFormatException
2
3class MyException : Throwable("Some message")
4
5fun testTryCatch(exception: Throwable) {
6    try {
7        throw exception
8    } catch (e: ArithmeticException) {
9        println("捕获到 ArithmeticException")
10    } catch (e: MyException) {
11        println("捕获到 MyException")
12    } catch (e: Throwable) {
13        println("捕获到某个异常")
14    }
15}
16
17fun main() {
18    testTryCatch(ArithmeticException())
19    // 捕获到 ArithmeticException
20    testTryCatch(MyException())
21    // 捕获到 MyException
22    testTryCatch(NumberFormatException())
23    // 捕获到某个异常
24}