Javascript 字符串替换为jquery辅助

我有一根这样的绳子

"/folder1/folder2/folder3/IMG_123456_PP.jpg"

我想使用JavaScript/jQuery将上述字符串中的

123456

替换为

987654

。整个字符串是动态的，因此无法进行简单的字符串替换。例如，字符串也可以是

"/folder1/folder2/folder3/IMG_143556_TT.jpg"
"/folder1/folder2/folder3/IMG_1232346_RR.jpg"

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有什么提示吗？

使用正则表达式

var str = '/folder1/folder2/folder3/IMG_123456_PP.jpg';

var newstr =  str.replace(/(img_)(\d+)(?=_)/gi,function($0, $1){
                                                  return $1 ? $1 + '987654' : $0;
                                                });

举例

---

也许更容易理解的是

var str = '/folder1/folder2/folder3/IMG_123456_PP.jpg';
var replacewith = '987654';
var newstr = str.replace(/(img_)(\d+)(?=_)/gi,'$1'+replacewith);

举例

编辑：

"/fo1/fo2/fol3/IMG_123456fgf_PP.jpg".replace(/\_\d{2,}[A-Za-z]*/,'_987654');

---

我相信有更好的方法可以做到这一点，但如果您总是尝试替换该文件的编号，而不管它们可能是什么，您可以使用以下拆分/联接组合：

str = "/folder1/folder2/folder3/IMG_143556_TT.jpg" //store image src in string
strAry = str.split('/') //split up the string by folders and file (as last array position) into array.
lastPos = strAry.length-1; //find the index of the last array position (the file name)
fileNameAry = strAry[lastPos].split('_'); //take the file name and split it into an array based on the underscores.
fileNameAry[1] = '987654'; //rename the part of the file name you want to rename.
strAry[lastPos] = fileNameAry.join('_'); //rejoin the file name array back into a string and over write the old file name in the original string array.
newStr = strAry.join('/');  //rejoin the original string array back into a string.

这样做的目的是，无论文件名的目录或原始名称是什么，都可以根据字符串的结构对其进行更改。因此，只要文件命名约定保持不变（带下划线），该脚本就可以工作

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请原谅我的发音B，我知道它不是很好，呵呵。

为什么123456被987654替换？插入的新字符串是否有逻辑？或者所有的案例都需要替换为987654？

\d+

不需要懒惰，因为

\uu

不是一个数字。@Kenny，的确。。但是积极的lookbehind在js正则表达式中也不起作用，所以我只是更新了一个替代方法..虽然OP没有指定，但它在

/folder99/folder88/folder77/IMG_123456; PP.jpg

中失败。但是如果他达到

folder10

？）感谢您的帮助-我如何才能避免名称的123456部分包含字母的情况-即IMG_123456D_PP.jpg？+1感谢您的工作（代码、注释）和负责：）

str = "/folder1/folder2/folder3/IMG_143556_TT.jpg" //store image src in string
strAry = str.split('/') //split up the string by folders and file (as last array position) into array.
lastPos = strAry.length-1; //find the index of the last array position (the file name)
fileNameAry = strAry[lastPos].split('_'); //take the file name and split it into an array based on the underscores.
fileNameAry[1] = '987654'; //rename the part of the file name you want to rename.
strAry[lastPos] = fileNameAry.join('_'); //rejoin the file name array back into a string and over write the old file name in the original string array.
newStr = strAry.join('/');  //rejoin the original string array back into a string.