String Conversions 1. Overview In this quick tutorial, we’re going to get familiar with a couple of ways to convertStringtoIntin Kotlin. 2.StringtoIntConversion In its simplest scenario,we can use thetoInt()extension function to convert aStringto its correspondingIntvalue. When theStringcontain...
在应用程序中,我们经常需要将日期字符串转换为日期对象。在 TypeScript 中,由于类型系统的存在,这个过...
tv_origin.text=origin.toString()varint:Int btn_int.setOnClickListener{int=origin.toInt();tv_convert.text=int.toString()}varlong:Long btn_long.setOnClickListener{long=origin.toLong();tv_convert.text=long.toString()}varfloat:Float btn_float.setOnClickListener{float=origin.toDouble().toFloat(...
扩展函数是定义在类的外面,这里定义一个 String 类的扩展函数,用来获取字符串的最后一个字符: package com.kotlin.lib._1_topextensionfunction fun String.lastChar(): Char { return this.get(this.length - 1) } 1. 2. 3. 4. 5. 把要扩展的类或者接口的名称,放到即将添加的函数前面。这个类或者接口...
Though the size ofLongis larger thanInt, Kotlin doesn't automatically convertInttoLong. Instead, you need to usetoLong()explicitly (to convert to typeLong). Kotlin does it for type safety to avoid surprises. val number1: Int = 55 val number2: Long = number1.toLong() ...
val brand: String, val price: Int ) var car: Car? = null fun funcExample() { car = Car("红旗", 199999) // let 闭包里可用 it 访问调用者,可返回闭包的执行结果 val carBrand = car?.let { "car's brand is ${it.brand}" } ...
// Inferred type: Map<String, Int> Map<String, Int>的泛型类型是从传递给Pair构造函数的参数的类型推断出来的。我们可能会想知道,如果用于创建map的推断类型的对不同会发生什么?第一对是Pair<String, Int>,第二对是Pair<String, String>: var map = mapOf("Mount Everest" to 8848, "K2" to "4017"...
Duration是如何做到不同单位的数据换算的,先看看Duration的创建函数和构造函数。toDuration把当前的值通过convertDurationUnit把时间换算成nanos或millis的值,再通过shl运算用来记录单位。 //Long创建 Duration publicfun Long.toDuration(unit: DurationUnit): Duration { ...
在Python中将字符串转换为整数的错误方法 (The Wrong Way to Convert a String to an Integer in Python) Programmers coming... Here, TypeError: must be str, not int indicates that the integer must first be converted to a string...在这里, TypeError: must be str, not int ,该整数必须先转换为...
String result = origin.substring(number, number+1); tv_convert.setText(result); 现在使用Kotlin实现上述需求,就简单多了,因为Kotlin允许直接通过下标访问指定位置的字符,代码如下: tv_convert.text = origin[number].toString() 同时,Kotlin也支持字符串通过get方法获取指定位置上的字符,代码如下: tv_convert.te...