2.1. Native contains Method First, using core Kotlin support, we can use the contains method that returns true or false depending on if the substring is contained in the string object that is calling: @Test fun `given a string when search for contained substrings then should return true`()...
drop(n: Int): String 去掉前n个字符,返回其余的字符串,等同于substring(n) //删掉前3个字符println(str.drop(3))//输出结果:456789 dropLast(n: Int): String 去掉后n个字符,返回其余的字符串,等同于substring(0, str.length – n) //删掉后4个字符println(str.dropLast(4))//输出结果:12345 dropWh...
1. 字符串截取 字符串截取操作可以使用substring、dropXXX系列和takeXXX系列方法 drop(n: Int): String 去掉前n个字符,返回其余的字符串,等同于substring(n) //删掉前3个字符 println(str.drop(3)) //输出结果:456789 1. 2. 3. dropLast(n: Int): String 去掉后n个字符,返回其余的字符串,等同于substrin...
operator fun Regex.contains(text: CharSequence) : Boolean { return this.containsMatchIn(text) } // 结合着 in 和 when 一起使用 when (input) { in Regex("[0–9]") -> println("contains a number") in Regex("[a-zA-Z]") -> println("contains a letter") } 1. 2. 3. 4. 5. 6...
valname:String?=nullwith(name){valsubName=name!!.substring(1,2) }// 使用之前可以检查它的可空性name?.run{valsubName=name.substring(1,2) }?:throw IllegalArgumentException("name mustnotbenull") 在这个例子当中,name?.run 会更好一些,因为在使用之前可以检查它的可空性。
var line: String? while (reader.readLine().also { line = it } != null) { // REG_SZ 表示这是一个字符串值 if (line!!.contains("REG_SZ")) { // 提取注册表项的值并比较 // 需要忽略大小写,因为 Windows 路径不区分大小写 val registryValue = line.substringAfter("REG_SZ").trim() ...
Kotlin String Operations It is very necessary to know about String Operations in programming applications. Following topics take you through some of the String Operations that are commonly used. Kotlin – Check if Two Strings are Equal Kotlin – Check if String contains Specified Substring ...
if (age <= 0) { throw IllegalArgumentException("age must not be negative") } // 使用 require 去检查 require(age > 0) { "age must be negative" } // 使用 checkNotNull 检查 val name: String? = null checkNotNull(name){ "name must not be null" ...
{ jarInput -> String jarName = jarInput.name String md5Name = DigestUtils.md5Hex(jarInput.file.getAbsolutePath()) if (jarName.endsWith(".jar")) { jarName = jarName.substring(0, jarName.length() - 4) } File dest = outputProvider.getContentLocation(jarName + md5Name, jarInput....
val name: String? = nullwith(name){val subName = name!!.substring(1,2)}// 使用之前可以检查它的可空性name?.run { val subName = name.substring(1,2) }?:throw IllegalArgumentException("name must not be null") 在这个例子当中,name?.run 会更好一些,因为在使用之前可以检查它的可空性。