正則表達式匹配行條目以空格填充在textarea的

Question

我有一個HTML文本區域，將有條目，可以如下所示：

google.com 
    youtube.com word word 
    netflix.com 
twitch.tv 
    vimeo.com word 
soundcloud.com word word 

我要做出特色，將通過列表的搜索url並刪除它的所有條目。要做到這一點，我首先需要一個正則表達式來查找第一個匹配項。請注意，我只需要並希望找到第一個匹配項。

該功能只能刪除完全匹配。也就是說，

DeleteEntry("youtube.com"); 

不要刪除第二行，但

DeleteEntry("youtube.com word word"); 

應該。

所以基本上，我需要匹配這一模式

(beginningOfString OR newlineChar) then (anyWhiteSpaceExceptNewline) then (ENTRY) then (anyWhiteSpaceExceptNewline) then (endOfString OR newlineChar) 

---

這是我迄今爲止

var expression = "\n|^[ \f\r\t\v]*" + entry + "[ \f\r\t\v]*\n|$"; 
var match = listbox.value.match(expression); 

它似乎沒有工作我期待的方式它來。

Answer 1

注意：如果要在字符串中使用\，則必須將其轉義。 "\some text"是錯誤的，但是"\\some text"是正確的。

var ta = document.getElementById("ta"), 
 
    inp = document.getElementById("inp"), 
 
    btn = document.getElementById("btn"); 
 
    
 
// escape text to be used inside RegeExp (from: https://stackoverflow.com/q/3115150/6647153) 
 
function escape(text) { 
 
    return text.replace(/[-[\]{}()*+?.,\\^$|#\s]/g, '\\$&'); 
 
} 
 

 
function deleteEntry(query) { 
 
    var text = ta.value; 
 
     
 
    var regexText = query.trim()         // remove surrounding spaces 
 
         .split(/\s+/)        // split into tokens ("a b c" becomes ["a", "b", "c"]) 
 
         .map(escape)        // escape the tokens ("a.com" becomes "a\\.c" so it'll be /a\.c/ where the '.' is regarded as litteral '.' not as the special character .) 
 
         .join("\\s+");        // joins the tokens together with \s+ (["a", "b", "c"] becomes "a\\s+b\\s+c" so it'll be /a\s+b\s+c/) 
 
     
 
    var regex = new RegExp("^\\s*" + regexText + "\\s*$", "gm"); // surrond regexText with ^\s* and \s*$ and use the g modifier for multiple matches and the m modifier for multiline text 
 
    
 
    ta.value = text.replace(regex, "");        // replace the matched text with "" and reassign it back to the textarea 
 
} 
 
    
 
btn.onclick = function() { 
 
    deleteEntry(inp.value);           // calling deleteEntry passing to it the input's value as the query 
 
}

textarea { 
 
    display: block; 
 
    width: 100%; 
 
    height: 100px; 
 
}

<textarea id="ta"> 
 
google.com 
 
    youtube.com word word 
 
    netflix.com 
 
twitch.tv 
 
    vimeo.com word 
 
soundcloud.com word word 
 
</textarea> 
 
<input id="inp"><button id="btn">Delete</button>