kotlin - 如何在 Kotlin 中将 String 转换为 Long？

Question

所以，由于缺乏像 Long.valueOf(String s) 这样的方法，我被卡住了。

如何在 Kotlin 中将 String 转换为 Long？

Answer 1

1. string.toLong()

Parses the string as a [Long] number and returns the result.

@throws NumberFormatException if the string is not a valid representation of a number.

2. string.toLongOrNull()

Parses the string as a [Long] number and returns the result or null if the string is not a valid representation of a number.

3. str.toLong(10)

Parses the string as a [Long] number and returns the result.

@throws NumberFormatException if the string is not a valid representation of a number.

@throws IllegalArgumentException when [radix] is not a valid radix for string to number conversion.

public inline fun String.toLong(radix: Int): Long = java.lang.Long.parseLong(this, checkRadix(radix))

4. string.toLongOrNull(10)

Parses the string as a [Long] number and returns the result or null if the string is not a valid representation of a number.

@throws IllegalArgumentException when [radix] is not a valid radix for string to number conversion.

public fun String.toLongOrNull(radix: Int): Long? {...}

5. java.lang.Long.valueOf(string)

public static Long valueOf(String s) throws NumberFormatException