Question

我正在替换字符串中的单词而我正在尝试根据'\b' + myword + '\b'进行匹配但是，当myword两端都有非单词字符时，这不起作用。

var myword1 = "testword,";
var myword2 = "(testword";
var testString = "<tag>asdftestword, is a (testwordasdf also (testword </tag> (testword, should be replaced everywhere there is a testword,)";

var rx1 = new RegExp(???(myword1) ,'g');
var rx2 = new RegExp(???(myword2) ,'g');
var result1 = testString.replace(rx1, "replacement");
var result2 = testString.replace(rx2, "replacement");

我希望结果是

result1 == "<tag>asdftestword, is a (testwordasdf also (testword </tag> (replacement should be replaced everywhere there is a replacement)"
result2 == "<tag>asdftestword, is a (testwordasdf also replacement </tag> replacement, should be replaced everywhere there is a testword,)"

Answer 1

testString.replace( new RegExp('\\b'+myword+'\\b','g'), "replacement");

但是，如果myword可能包含正则表达式中特殊的字符（例如parens，句点，括号等），那么您需要escape them first：

RegExp.escape = function(text) {
  if (!RegExp.sRE) {
    var chars = '/.*+?|()[]{}\\'.split('');
    RegExp.sRE = new RegExp('\\'+chars.join('|\\'), 'g');
  }
  return text.replace(RegExp.sRE, '\\$&');
}

var re = new RegExp('\\b'+RegExp.escape(myword)+'\\b','g');

Answer 2

你不需要正则表达式。只需使用普通的字符串替换：

var myword = "testword,";
var testString = "<tag>asdftestword, is a testword</tag> (testword, should be replaced everywhere there is a testword,)";

var result = testString.replace( myword , "replacement");

Answer 3

var rx = new RegExp('\\b' + myword ,'g');
var result = testString.replace(rx, 'replacement');

Answer 4

好的，我终于弄明白了。看起来它太复杂了，只需要一个我需要多个的RegExp！

在行动Here

中查看

function EscapeRegex(text) {
    if (!RegExp.sRE) {
    var chars = '/.*+?|()[]{}\\'.split('');
    RegExp.sRE = new RegExp('\\'+chars.join('|\\'), 'g');
    }
    return text.replace(RegExp.sRE, '\\$&');
}

function ReplaceWholeWord(subjectString, wordtofind, replacement){
    var escapedWord = EscapeRegex(wordtofind);
    //simplest scenaro, word to find has non-word characters at begining and end - do basic replace
    if(regexIndexOf(escapedWord, '[^\\w]', 0) == 0 && regexLastIndexOf(escapedWord, '[^\\w]', 0) == wordtofind.length - 1){
        subjectString = subjectString.replace(new RegExp(escapedWord, 'g'), replacement);
    }
    //word to find begins with non-wordcharacter
    else if(regexIndexOf(escapedWord, '[^\\w]', 0) == 0){
        var index = regexIndexOf(subjectString, escapedWord+'[^\\w]', index);
        while(index > 0){
            subjectString = subjectString.substring(0, index) + replacement + subjectString.substring(index + wordtofind.length);
            index = regexIndexOf(subjectString, escapedWord+'[^\\w]', index);
        }
    }
    //word to find ends with non-wordcharacter
    else if(regexLastIndexOf(escapedWord, '[^\\w]', 0) == wordtofind.length - 1){
        var index = regexIndexOf(subjectString, '[^\\w]'+escapedWord, index);
        while(index > 0){
            subjectString = subjectString.substring(0, index) + replacement + subjectString.substring(index + myword.length + 1);
            index = regexIndexOf(subjectString, escapedWord+'[^\\w]', index);
        }
    }
    //word is normal
    else{
        var index = regexIndexOf(subjectString,'[^\\w]'+escapedWord+'[^\\w]', index);
        while(index >= 0){
            subjectString = subjectString.substring(0, index + 1) + replacement + subjectString.substring(index + wordtofind.length + 1);
            index = regexIndexOf(subjectString,'[^\\w]'+escapedWord+'[^\\w]', index);
        }
    }
    return subjectString;
}

如何匹配包含非单词字符的单词？

4 个答案: