通过JavaScript在文本框中禁用退格 [英] Disable backspace in textbox via javascript

问题描述

我有一个由Ajax控件工具包日历扩展的文本框。

I have a textbox which is extended by an Ajax Control Toolkit calendar.

我想使它使得用户不能编辑文本框和将要代替使用日历扩展器输入

I want to make it so that the user cannot edit the textbox and will have to instead use the calendar extender for input.

我设法阻止除退格键全部！

I have managed to block all keys except backspace!

这是我迄今为止：

<asp:TextBox ID="TextBox1" runat="server" onKeyPress="javascript: return false;" onKeyDown="javascript: return false;" onPaste="javascript: return false;" />

我怎么会还使用javascript文本框内禁用退格？

How would I also disable backspace within the textbox using javascript?

修改

做了编辑，因为我需要在JavaScript的解决方案。

Made an edit since I need a solution in javascript.

修改

原来，的onkeydown =JavaScript的：返回false;确实工作。我不知道为什么它不工作之前。我试图用一个新的文本框，并阻止退格罚款。很抱歉给大家谁张贴的答案希望能得到一些代表ESP。之后，我标志着它赏金。

It turns out that onKeyDown="javascript: return false;" DOES work. I have no idea why it wasn't working before. I tried using a new textbox and it blocked backspaces fine. So sorry to everyone who posted an answer hoping to get some rep esp. after I marked it for bounty.

我现在的文本框（似乎）以阻止所有的按键，也仍然与日历扩展工作。

My textboxes now (seem) to block ALL keystrokes and also still work with the calendar extender.

推荐答案

ZX12R接近。这是正确的解决办法：

ZX12R was close. This is the correct solution:

文本框是这样的：

    <asp:TextBox ID="TextBox1" runat="server" onKeyDown="preventBackspace();"></asp:TextBox>

和脚本如下：

<script type="text/javascript">
    function preventBackspace(e) {
        var evt = e || window.event;
        if (evt) {
            var keyCode = evt.charCode || evt.keyCode;
            if (keyCode === 8) {
                if (evt.preventDefault) {
                    evt.preventDefault();
                } else {
                    evt.returnValue = false;
                }
            }
        }
    }
</script>

首先，退格不会对重点preSS才能通过，所以你必须使用Key向下。

First of all, the backspace wont come through on Key Press, so you have to use Key Down.

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