在第X个位置间隔使用正则表达式替换字符串(javascript) [英] replacement of string using regular expression at Xth position intervals (javascript)

问题描述

我非常感谢社区提供的一些帮助，以使用javascript正则表达式在xth位置间隔处替换字符串.例如，如果字符串长度为161并且替换文本为<br />，则regex将使用此替换文本替换在第40、80、120和160位的字符串.使用正则表达式可以吗?

I would very much appreciate some assistance from the community on replacing a string at xth position intervals, using javascript regex. For example, if the string length is 161 and the replacement text is <br />, regex would replace the string at the 40th, 80th, 120th, and 160th positions with this replacement text. Is this possible using regex?

非常感谢您.

推荐答案

将<br />添加到第40位的方法是使用以下行:

A method to add <br /> at ever 40th position is by using the following line:

string = string.replace(/([\S\s]{40})/g , "$1<br />");

如果要动态设置位置，请使用:

If you want to dynamically set the position use:

var positions = 40;
var pattern = new RegExp("([\\s\\s]{" + positions + "})", "g");
string = string.replace(pattern , "$1<br />");

代码说明:

1. replace函数的第一个参数是RegExp:
   • ([\S\s] =所有非空白字符和空白字符=每个字符).
   • {40} = 40个字符
   • g标志的意思是:全局匹配，即:匹配所有可能出现的情况
   • RegExp内的括号表示:创建一个组.此组以后可以由$1(第一组)
   引用

1. The first argument of the replace function is a RegExp:
   • ([\S\s] = all non-whitespace and white-space characters = every character).
   • {40} = 40 characters
   • The g flag means: global match, ie: match every possible occurence
   • The parentheses inside the RegExp means: Create a group. This group can later be referred by $1 (first group)

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