Kotlin本机iOS字符串格式与vararg [英] Kotlin Native iOS string formatting with vararg
问题描述
基于此问题,有关使用NSString
格式,我尝试在使用vararg
时实现用于格式化的多平台实现,到目前为止还没有运气.
Based on this issue about using NSString
formatting I try to implement multiplatform implementation for formatting when using vararg
, with no luck so far.
我做了
- 添加了FoundationInterop.def
language = Objective-C
---
#import <Foundation/NSString.h>
NSString* format(NSString* format, ...) {
va_list args;
va_start(args, format);
NSString* result = [[NSString alloc] initWithFormat:format arguments:args];
va_end(args);
return result;
}
- 将其编译为gradle
targets {
final def iOSTarget = System.getenv('SDK_NAME')?.startsWith("iphoneos") \
? presets.iosArm64 : presets.iosX64
// https://kotlinlang.org/docs/reference/mpp-dsl-reference.html#native-targets
fromPreset(iOSTarget, 'ios') {
binaries {
}
compilations.main.cinterops {
FoundationInterop {
}
}
}
}
- 在
commonMain
中创建了
StringExtensions.kt
expect class StringType
expect fun String.format(format: String, vararg args: Any?): StringType?
- 在
iosMain
- in
iosMain
actual typealias StringType = String
/**
* https://github.com/JetBrains/kotlin-native/issues/1834
*/
actual fun String.format(format: String, vararg args: Any?): StringType? {
return FoundationInterop.format(format, args as Any)
}
- 示例
val fmt = "http://geomag.bgs.ac.uk/web_service/GMModels/igrf/13/?latitude=%f&longitude=%f&altitude=0&date=%d-%02d-%02d&format=json"
val url = fmt.format(urlFmt, 59.127934932762166, 38.00503518930868, 2020, 1, 3)
- 输出-如您所见,由于某种原因没有发生值替换
- output - as you see no values substitutions occured for some reason
http://geomag.bgs.ac.uk/web_service/GMModels/igrf/13/?latitude=0.000000&longitude=0.000000&altitude=0&date=43344272-198763328-00&format=json
修改
stringWithFormat
给出相同的结果
actual fun String.format(format: String, vararg args: Any?): StringType? {
return NSString.stringWithFormat(format, args as Any)
}
编辑2
已创建的问题 https://youtrack.jetbrains.com/issue/KT-42925
推荐答案
我确认您对NSString.stringWithFormat
的看法.正如我们在JB官方答复中所读到的那样,该功能缺失
Svyatoslav Scherbina,我们可以在这里关注您的问题: KT-42925
I confirm what you say about NSString.stringWithFormat
. The feature is missing as we read in the JB offical answer from
Svyatoslav Scherbina and we could follow the issue from you here: KT-42925
作为一个可怕的解决方法,我建议使用类似的方法(警告:并不详尽,没有很多索引计数检查...)
As an awful workaround, I was suggesting something like that (WARNING: not exhaustive, without many index count checks...)
import platform.Foundation.NSString
import platform.Foundation.stringWithFormat
actual typealias StringType = String
actual fun String.format(format: String, vararg args: Any?): StringType? {
var returnString = ""
val regEx = "%[\\d|.]*[sdf]|[%]".toRegex()
val singleFormats = regEx.findAll(format).map {
it.groupValues.first()
}.asSequence().toList()
val newStrings = format.split(regEx)
for (i in 0 until args.count()) {
val arg = args[i]
returnString += when (arg) {
is Double -> {
NSString.stringWithFormat(newStrings[i] + singleFormats[i], args[i] as Double)
}
is Int -> {
NSString.stringWithFormat(newStrings[i] + singleFormats[i], args[i] as Int)
}
else -> {
NSString.stringWithFormat(newStrings[i] + "%@", args[i])
}
}
}
return returnString
}
但是请看它是否对您来说是有效的解决方法.
But look if it could be a valid workaround for you.
这篇关于Kotlin本机iOS字符串格式与vararg的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!