Javascript和正則表達式替換文本

Question

先生， 我是做用JavaScript。我的一個項目想與regex.in一個段落，以取代文本，我想使用JavaScript

替換一些詞如：

var str =" Would you like to have responses to your questions |code Would you like to have responses to your questions code| Would you like to have responses to your questions " 

var n=str.replace("to","2"); 

這裏所有的「到」將replaced.We不想之間刪除|代碼到代碼|請幫助我的任何一個.....

Answer 1

我認爲你不應該依賴這些類型的任務正則表達式，因爲它會過於複雜，因此緩慢。無論如何，如果你的表達是正確的（即，對於每一個"|code"有一個"code|"有沒有嵌套code標籤），你可以試試這個：

var n = str.replace(/to(?!(?:\|(?!code)|[^\|])*code\|)/g, "2"); 

不僅是複雜的，但它很難維持。在這些情況下做的最好的事情是你的字符串分割，以塊：

var chunks = [], i, p = 0, q = 0; 
while ((p = str.indexOf("|code", p)) !== -1) { 
    if (q < p) chunks.push(str.substring(q, p)); 
    q = str.indexOf("code|", p); 
    chunks.push(str.substring(p, p = q = q + 5)); 
} 
if (q < str.length) chunks.push(str.substring(q)); 

// chunks === [" Would you like to have responses to your questions ", 
//    "|code Would you like to have responses to your questions code|", 
//    " Would you like to have responses to your questions "] 

注：str.replace("to", "2")不不取代"to"每一次出現，但只有第一個。

Answer 2

，如果你想將所有「到」更換成2，這將是代碼

var str =" Would you like to have responses to your questions |code Would you like to have responses to your questions code| Would you like to have responses to your questions"; 
var n=str.replace(/to/g,"2");