找到< textarea>的当前行的值使用javascript [英] Find value of current line of a <textarea> using javascript

问题描述

如何找到textarea的当前行的值？

我知道我必须找到插入位置，但随后找到它之前的所有内容最后的\ n及其后的所有内容到下一个\ n。

我该怎么做？

  var caretPos = 53， //但是你得到它
 start，结束
; 
 
 for（start = caretPos; start> = 0&& myString [start]！=\ n; --start）; 
 for（end = caretPos; end< myString.length&& myString [end]！=\ n; ++ end）; 
 
 var line = myString.substring（start + 1，end  -  1）; 
  

How can I find the value of the current line of a textarea?

I know I have to find the caret position, but then find everything before it up to the last \n and everything after it to the next \n.

How can I do this?

解决方案

A simple way would be to just loop:

var caretPos = 53, // however you get it
    start, end
;

for (start = caretPos; start >= 0 && myString[start] != "\n"; --start);
for (end = caretPos; end < myString.length && myString[end] != "\n"; ++end);

var line = myString.substring(start + 1, end - 1);

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