Why this code not Work

Question

1.00/5 (1 vote)

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hello

why this code Not work :

JavaScript

$(document).ready(function () {

        var textbox = document.getElementById("text1");
        //event key down and key up and keypress
        textbox.onkeydown(function () {
            alert();
        });

    });

error:

TypeError: textbox is null

html mvc :

Razor

@{
    ViewBag.Title = "Index";
}

<h2>Index</h2>

<input type="text" id="text1 " />

i want to learn javaascript and jquery what is the best book (2013 or 2014) for them ?

Posted 2-May-14 5:15am

NorouziFar

Updated 2-May-14 5:25am

v3

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Comments

CHill60 2-May-14 11:20am

You haven't got an element called "text1" ... is it "Text1" perhaps?

thatraja 2-May-14 11:21am

Share the HTML content of page in your question

CHill60 2-May-14 11:30am

Change id="text1 " to id="text1"

NorouziFar 2-May-14 11:33am

book?

CHill60 2-May-14 11:40am

Have a look here A Gallery of Useful Programming Books[^] - did the fix work?

Аslam Iqbal 3-May-14 1:42am

exact point

NorouziFar 2-May-14 11:52am

tanks very please give me your solution i rate you

3 solutions

Solution 1

Try this:
var textbox = $('#text1');

Posted 2-May-14 5:35am

Tanuj Rastogi

Comments

Sergey Alexandrovich Kryukov 2-May-14 18:33pm

5ed.
I added Solution 2 with some explanations to it.
—SA

Solution 3

You need to fix two errors.
1. correct the text id, remove the extra space.

<input type="text" id="text1" />

2. assign a function to onkeydown:

C#

textbox.onkeydown = function () {
            alert("onkeydown");
        };

Posted 3-May-14 21:15pm

Xiao Ling

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Sergey Alexandrovich Kryukov · Accepted Answer · 2014-05-02T12:32:00

If you already using jQuery, using document.getElementById is just pointless; it is already done in more general way, through selectors:
http://api.jquery.com/category/selectors[^].

If you know the id value, you can use the id selector (see also the sample in Solution 1): http://api.jquery.com/id-selector/[^].

—SA