dapatkan string di antara dua string menggunakan jquery

Diuji dan sekarang berfungsi (versi asli tidak mengulangi semua elemen .comment-body, atau menemukan substring() dengan benar):

var divString, imgString;
$('.comment-body').each(
    function(){
        divString = $(this).text();
        imgString = divString.substring(divString.indexOf('[img]') + 5,divString.indexOf('[/img]'));
        console.log(imgString);
    });

JS Fiddle.

Diedit karena saya sedikit bosan, sehingga mengubah fungsi di atas menjadi fungsi yang lebih umum:

function findStringBetween(elem,bbTagStart,bbTagClose){
    var tag = bbTagStart;

    function impliedEndTag(tag){
        var impliedEnd = tag.replace(tag.substring(0,1),tag.substring(0,1) + '/');
        return impliedEnd;
    }

    var endTag = bbTagClose || impliedEndTag(tag);

    var divString = $(elem).text();
    var tagString = divString.substring(divString.indexOf('[img]') + tag.length,divString.indexOf('[/img'));
    return tagString;
}
$('.comment-body').each(
    function(){
        /* call with two, or three arguments (the third is the optional 'bbTagClose':
            1. elem = this, the DOM node,
            2. '[img]' = whatever bbCode thing you want to use (I'm not sure what's available),
            3. 'bbTagClose' = the end tag of the bbCode, assuming that the end-tag is the same as
                the opening tag, except with a '/' as the second character, the impliedEndTag() function
                will take care of it for you.
        */
        var elemString = findStringBetween(this,'[img]');
        $(this).replaceWith('<img src="' + elemString + '" class="commentimg" data-src2="'+ elemString +'"/>');
    });

Demo JS Fiddle.

...fungsinya menambahkan '' ke setiap div dengan badan komentar kelas bagaimana saya hanya bisa menerapkan kode ke elemen badan komentar yang berisi [img]gambar src di sini[/img]

Saya telah menambahkan beberapa pemeriksaan kewarasan, untuk memastikan bahwa fungsi mengembalikan false ketika tag yang ditentukan tidak ditemukan:

function findStringBetween(elem,bbTagStart,bbTagClose){
    var tag = bbTagStart;

    function impliedEndTag(tag){
        var impliedEnd = tag.replace(tag.substring(0,1),tag.substring(0,1) + '/');
        return impliedEnd;
    }

    var endTag = bbTagClose || impliedEndTag(tag);
    var divString = $(elem).text().trim(); // added .trim() to remove white-spaces

    if (divString.indexOf(tag) != -1){ // makes sure that the tag is within the string
        var tagString = divString.substring(divString.indexOf('[img]') + tag.length,divString.indexOf('[/img'));
        return tagString;
    }
    else { // if the tag variable is not within the string the function returns false
        return false;
    }
}
$('.comment-body').each(
    function(){
        /* call with two, or three arguments (the third is the optional 'bbTagClose':
            1. elem = this, the DOM node,
            2. '[img]' = whatever bbCode thing you want to use (I'm not sure what's available),
            3. 'bbTagClose' = the end tag of the bbCode, assuming that the end-tag is the same as
                the opening tag, except with a '/' as the second character, the impliedEndTag() function
                will take care of it for you.
        */
       var imgLink = findStringBetween(this,'[img]');
        if (imgLink){ // only if a value is set to the variable imgLink will the following occur
            $(this).replaceWith('<img src="' + imgLink + '" class="commentimg" data-src2="'+ imgLink+'"/>');
        }
    });

Demo JS Fiddle.

[Apakah] ada cara untuk mencegahnya menghapus teks dalam contoh 'teks acak di sini'[?]

Ya, Anda dapat .append(), atau .prepend() gambar ke dalam elemen, setelah terlebih dahulu memperbarui teks div, dalam kode berikut saya telah menghapus string [img]...[/img], membiarkan hanya teks lainnya, disisipkan teks itu ke dalam elemen .comment-body dan kemudian menambahkan img ke dalamnya, alih-alih menggunakan replaceWith():

function findStringBetween(elem,bbTagStart,bbTagClose){
    var tag = bbTagStart;

    function impliedEndTag(tag){
        var impliedEnd = tag.replace(tag.substring(0,1),tag.substring(0,1) + '/');
        return impliedEnd;
    }

    var endTag = bbTagClose || impliedEndTag(tag);
    var divString = $(elem).text().trim();

    if (divString.indexOf(tag) != -1){
        var elemInfo = [];
        elemInfo.imgString = divString.substring(divString.indexOf(tag) + tag.length,divString.indexOf(endTag));
        elemInfo.text = divString.replace(tag + elemInfo.imgString + endTag, '');
        return elemInfo;
    }
    else {
        return false;
    }
}
$('.comment-body').each(
    function(){
        /* call with two, or three arguments (the third is the optional 'bbTagClose':
            1. elem = this, the DOM node,
            2. '[img]' = whatever bbCode thing you want to use (I'm not sure what's available),
            3. 'bbTagClose' = the end tag of the bbCode, assuming that the end-tag is the same as
                the opening tag, except with a '/' as the second character, the impliedEndTag() function
                will take care of it for you.
        */
       var elemInfo = findStringBetween(this,'[img]');
        if (elemInfo.imgString){
            // or .prepend() if you prefer
            $(this).text(elemInfo.text).append('<img src="' + elemInfo.imgString + '" class="commentimg" data-src2="'+ elemInfo.imgString +'"/>');
        }
    });

Demo JS Fiddle.

Referensi:

• jQuery stuff:
  • append().
  • each().
  • prepend().
  • replaceWith().
  • text().
• JavaScript (all at the Mozilla Developer Network's JavaScript documentation resource:
  • indexOf().
  • length.
  • replace().
  • substring().
  • trim().

Jawaban alternatif dari yang ditulis oleh David Thomas.

Cara lain untuk mengimplementasikan kode ini adalah dengan menggunakan ekspresi reguler.

// inputText - input text that contains tags
// tagName - name of the tag we want to replace
// tagReplace - replacement for the tag, "$1" will get replaced by content of the tag
function replaceText(inputText, tagName, tagReplace) {
  var regExp = new RegExp('\\[' + tagName+ '\\]([^\\[]*)\\[\/' + tagName + '\\]', 'g');
  return inputText.replace(regExp, tagReplace);
}

$('.comment-body').each(function() {
  var $this = $(this);
  var replacedText = replaceText($this.text(), 'img', '<img src="$1" \/>');
  $this.html(replacedText);
});

Penerapan ini juga akan menggantikan beberapa tag dalam komentar.

Lihat cuplikan kode INI.

Catatan 1:

Saat menerapkan kode ini di lingkungan nyata, harap pertimbangkan untuk membuat ekspresi reguler terlebih dahulu untuk semua nama tag yang ditangani di luar replaceText() sehingga regExp tidak akan dibuat setiap kali replaceText() dipanggil.

Catatan 2:

Untuk mendapatkan hasil yang persis seperti pada perubahan pertanyaan:

  var replacedText = replaceText($this.text(), 'img', '<img src="$1" \/>');

to

  var replacedText = replaceText($this.text(), 'img', '<img src="samesrc" class="commentimg" data-src2="$1" \/>');

Fungsi ini menemukan kode bb tertentu dalam string apa pun dan jika Anda mau, Anda dapat mengonfigurasinya untuk mengganti atau mengekstrak konten sebagai array dari kode bb tersebut.

//search str 
var search_str = "I love this [img]question.png[/img] Flowers, and [img]answer_1-1.png[/img] you say is that [img]answer_2-1.png[/img] good Point."
//using example
var str = bbcode_search_and_replace($('#search_str').text(),"[img]","[/img]");
$('#search_str').html(str);

function bbcode_search_and_replace(search_str, bb_opening_tag, bb_closing_tag) {
            //search str length
           var sLength = String(search_str).length;
           //bbcode opening tag length
           var fPart_length = String(bb_opening_tag).length;
           //bbcode closing tag length
           var ePart_length = String(bb_closing_tag).length;
           //position index for opening tag 
           var start_idx = 0;
           //position index for closing tag 
           var end_idx = 0; 
           //searching index for opening tag
           var pos_sIdx = 0;
           //position index for closing tag
           var pos_eIdx = 0;
           //var replacement = '[image]';
           var arr = [];
           var idx = 0;           

           //loop
           while(start_idx !== -1) {
               arr[idx] = {};                  

               start_idx = String(search_str).indexOf(bb_opening_tag,pos_sIdx);
               //check for ending
               if(start_idx === -1) {
                   //if exist, last str after closing tag
                   if(idx > 0) arr[idx]['str'] = search_str.substring(pos_sIdx);
                   console.log("arr[idx]['str'] = " + arr[idx]['str']);
                   break;
               }
               //end position index
               pos_eIdx = start_idx + fPart_length;
               end_idx = String(search_str).indexOf(bb_closing_tag,pos_eIdx);                   
               //save str inside bbtags
               arr[idx]['str'] = search_str.substring(pos_sIdx, start_idx);
               console.log("arr[idx]['str'] = " + arr[idx]['str']);
               arr[idx]['src'] =  "<img src = 'img/" + search_str.substring(start_idx + fPart_length, end_idx) + "' />";
               console.log("arr[idx]['src'] = " + arr[idx]['src']);
               arr[idx]['pos_start'] = start_idx + fPart_length;
               arr[idx]['pos_end'] = end_idx;                                

               //Update array and start pos indexes
               idx++;
               pos_sIdx = end_idx + ePart_length;                
          }

           var k = 0;
           var str = "";
           while(k < arr.length) {
               if(arr[k]['src'] === undefined) arr[k]['src'] = "";
               str += arr[k]['str'] + arr[k]['src'];
               k++;
           }

           return str;
        }  

Gunakan fungsi JavaScript match(), sangat mudah digunakan

Seperti jika Anda memiliki string "Rubah coklat yang cepat melompati anjing yang malas."

& Anda memerlukan teks antara "cepat" dan "malas"

Gunakan di bawah ini

<script type="text/javascript">
   var myStr = "The quick brown fox jumps over the lazy dog.";
   var subStr = myStr.match("quick(.*)lazy");
   alert(subStr[1]);
</script>

Semoga membantu!!