Get js Code _ form effects of the text in line n of the textarea tag

The code used to obtain the text of line n of the textarea tag is very good and compatible with firefox.

<Textarea id = "textareaobj"> 1. You are welcome to the feet home. 2. A large number of servers have been added recently, provide better speed 3. The network speed is too slow </textarea> <script type = "text/javascript"> str = document. getElementById ("textareaobj "). value; // obtain the text field content if (document. all) {// if it is IE, how to determine the browser type, find the code arr = str. split ("\ r \ n");} else {// firfox arr = str. split ("\ n");} // obtain the content of line n. Note that n starts from 0. alert (arr [0]) script
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Core code:

The Code is as follows: