爲什麼我的Javascript警報不顯示？

Question

基本上，我試圖通過PHP調用Javascript警報。雖然，警報根本不起作用。

這是動態創建警報

echo "<script>alert('Uploaded file was not in the correct format\n\nExample of the correct format:\nquestion1,answer1,answer2,answer3,answer4\n 
question2,answer1,answer2,answer3,answer4\nquestion3,answer1,answer2,answer3,answer4')</script>"; 

我發現，如果我改變了警惕這一點，它完美的作品我的回聲聲明：

echo "<script>alert('Uploaded file was not in the correct format')</script>"; 

我相信這是一個問題換行符。

我改變了我的代碼，這一點，但仍然沒有運氣：

echo "<script>alert('Uploaded file was not in the correct format\\nExample of the correct format:\\nquestion1,answer1,answer2,answer3,answer4\\n 
question2,answer1,answer2,answer3,answer4\\nquestion3,answer1,answer2,answer3,answer4')</script>"; 

我得到的錯誤：

SyntaxError: unterminated string literal 
[Break On This Error] 

alert('Uploaded file was not in the correct format\nExample of the 
------^ 

createplay.php (line 1, col 6) 

有沒有人有這是爲什麼不工作有什麼建議？在線搜索範圍很廣，找不到解決方案。

在此先感謝！

Answer 1

您的\n字符正被PHP的文字換行替換。

字符串文字內部的未轉義文字換行是JavaScript中的錯誤。使用\\n向JavaScript發送換行符轉義序列。

Answer 2

嘗試類似的東西：

<? 
    echo "<script>alert('Uploaded file was not in the correct format\\n\\nExample of the correct format:\\nquestion1,answer1,answer2,answer3,answer4\\n 
    question2,answer1,answer2,answer3,answer4\\nquestion3,answer1,answer2,answer3,answer4')</script>"; 
    ?> 

Answer 3

爲了增加昆汀的回答，會切換單和雙引號也能夠解決問題？

Answer 4

在\ n和下一個字符之間放一個空格，它將起作用。我試過你的代碼在我的系統上，它的工作