带有for循环的javascript，用于标记表单textarea中的文本

Question

I have a javascript that is to be used to tag text in a textarea when a user clicks a button. Right now I have only gotten it to work for one button. There are 8 buttons that need to be able to tag in total but I don't want to repeat the same code over and over for each button id, so I tried a for loop but this didn't work. I'm not quite sure why though.

These are the button ids: edit-button0, edit-button1, edit-button2, ...,edit-button8

I've added an alert in the for loop to check the button id.

No matter which button I click later it says button id is edit-button8, and it adds the tag connected to that button.

Any ideas why this doesn't work or how I should do it instead.

/*globals document*/
(function ($) {
    "use strict";
    $(document).ready(function () {

            for (i=0;i<8;i++) {

                $("#edit-button"+i).click(function () {
                        alert("#edit-button"+i);
                        var tag = $("#edit-button"+i).attr("value");
                        var id = "protocol"; /* id of textarea */

                        var element  = document.getElementById(id); /* HTML element object */
                        var start    = element.selectionStart;      /* start pos of selection */
                        var end      = element.selectionEnd;        /* end pos of selection */
                        var text     = element.value;           /* whole text */

                        var prefix   = text.substring(0, start);    /* part before selection */
                        var selected = text.substring(start, end);  /* selected text */
                        var suffix   = text.substring(end);         /* part after selection */
                        /* insert tags in selection */
                        selected     = "["+tag+"]" + selected + "[/"+tag+"]";

                        /* update HTML object */
                        element.value      = prefix + selected + suffix; /* selected text */

                        element.selectionStart = start;                      /* new start pos */
                        element.selectionEnd   = start + selected.length;    /* new end pos */


                        return false;
                    });
            }
    });
})(jQuery);

Answer 1

You could give all the buttons a class .tagButtons and then use .each() in jQuery to loop over them like this

$('.tagButtons').each(function(){ 
     $(this).click(function(){


             var tag = $(this).attr("value");
             var id = "protocol"; /* id of textarea */  

             var element  = document.getElementById(id);                         
             var start    = element.selectionStart;     
             var end      = element.selectionEnd;       
             var text     = element.value;                                             
             var prefix   = text.substring(0, start);   
             var selected = text.substring(start, end);                             
             var suffix   = text.substring(end);    
             selected     = "["+tag+"]" + selected + "[/"+tag+"]";                                                    

             element.value      = prefix + selected + suffix;  

             element.selectionStart = start;                                   
             element.selectionEnd   = start + selected.length;    

             return false;

     });
}); 

EDIT -

As an alternative and to help in the future, i think the issue with your code was your for loop. Have a look at this jsFiddle example to show how the loop should look.