删除一些字符后如何调整字符串中的索引? [英] How to adjust index in a string after removing some characters?

问题描述

我对正则表达式和文本操作很陌生，所以这对很多人来说可能是微不足道的，但对我来说却是一件很麻烦的事情.

I am very new to regex and text manipulation so this might be trivial for many but it is turning out to be quite a nuisance for me.

我有一个像这样的字符串:

I have a string like so:

*text* text text text text *text*

*text* text text text *text*

其中带 * 的黑白文本表示必须为粗体的文本
所以期望的输出是

where the text b/w the * denotes the text that has to be bold
So the desired output is

text text text text text

text text text text text

我已经使用以下代码完成了一半

I am halfway there using the following code

 val string = "*text* text text text *text*"
        val pattern = Pattern.compile("\\*")
        val matcher = pattern.matcher(string)
        val spannableString = SpannableString(string)
        var counter = 0
        val indexes = IntArray(1)

        while (matcher.find()) {
                if(counter==0){
                    indexes[0]=matcher.start()
                    counter+=1
                }else if(counter==1){
                spannableString.setSpan(
                    StyleSpan(Typeface.BOLD),
                    indexes[0],matcher.start(),
                    Spannable.SPAN_INCLUSIVE_EXCLUSIVE)
               counter+=1

            }
            if(counter==2){
                counter=0
            }
        }
        textView.text = spannableString
    }

现在的输出是
*text* text text text *text*(* 也是粗体)
我想删除 * 的
我打算使用

The output right now is
*text* text text text *text* (the *s are bold as well)
I want to remove the *'s
I intend to use

val spannableString = SpannableString(string.replace("*",""))

删除*，但在那之后，我无法调整需要传递的索引.我该怎么做?或者，还有更好的方法?非常感谢任何帮助

to remove the *'s but after that, I am not able to adjust the indexes that need to be passed on. How do I do it? or is there a better way? Any help is greatly appreciated

推荐答案

IMO 你真的不需要正则表达式来解决你的问题(有句名言 如果你想用正则表达式解决问题，现在你有两个问题"，我经常使用正则表达式来表示同意和不同意).

IMO you don't really need a regex to solve your problem (There's a famous saying "If you're trying to solve a problem with RegEx, now you have 2 problems", and I use RegExs frequently enough to both agree and disagree).

您可以在循环中的 String 中使用 indexOf 方法 (Java, Kotlin) 找到 * s，同时在 SpannableStringBuilder:

You can use the indexOf method in String in a loop (Java, Kotlin) to find the *s, while constructing your end result in a SpannableStringBuilder:

• 保持一个变量指向当前跨度的开头(如果没有打开的跨度，则为 -1).
• 在每次迭代中，您都使用 indexOf 从找到的最后一个索引开始.
• 每次找到开头的 * 时，您都会将最后一个位置到当前位置的文本附加到您的构建器中.
• 每次找到结束的 * 时，都将开头 * 的文本附加到接近的文本，并将其设置为粗体.
• 如果在迭代中没有找到 *，则将最后一站的所有内容附加到构建器
• 如果您到达字符串的末尾并且有一个从未关闭的打开的 * ，那么您就知道发生了错误.您可以应用或不应用粗体跨度(或 throw).

• Keep a variable pointing to the start of the current span (or -1 if no open spans).
• In every iteration, you use indexOf starting from the last index found.
• Every time you find an opening * you append the text from the last position to the current one to your builder.
• Every time you find a closing * you append the text from the opening * to the closer, and set it as a bold span.
• If you don't find a * at an iteration you append everything from the last stop to the builder
• If you reach the end of the string and have an open * that was never closed you know you have an error. You can either apply a bold span or not (or throw).

希望这会有所帮助.

另外，请不要用指向您的链接的其他问题劫持.

Also, please don't hijack other questions with links to yours.

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