Javascript 对于 input type="number" 如何将默认值设置为 0

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时间:2020-08-23 17:03:05  来源:igfitidea点击:

for input type="number" how to set default value to 0

javascripthtmlangularjs

提问by NiksJ

For a textbox that accept numbers as shown below, how can the default value be set to 0?

对于如下所示的接受数字的文本框,如何将默认值设置为 0?

<input name="smtpPort" type="number" id="smtpPort" size="30" maxlength="50" class="input-full" tabindex="4" value="{{model.PortNumber}}">

Though the value in DB is null, it still shows 0 in textbox.

尽管DB中的值为空,但在文本框中仍然显示为0。

Any help would be appreciated.

任何帮助,将不胜感激。

回答by zessx

HTML attribute to set a default value is value:

设置默认值的 HTML 属性是value

<input type="number" value="1">

You're setting this default value to null, and nothing (in HTML) can change it to zero (or anything else).
You must fix the value in your database, or in your template engine (something like {{model.PortNumber || 0}}).

您将此默认值设置为null,并且(在 HTML 中)没有任何东西可以将其更改为零(或其他任何内容)。
您必须修复数据库或模板引擎中的值(例如{{model.PortNumber || 0}})。

At least, you can force your field to be filled with requiredattribute:

至少,您可以强制您的字段填充required属性:

<input type="number" required value="">

回答by kravits88

<input name="smtpPort" type="number" id="smtpPort" size="30" maxlength="50" class="input-full" tabindex="4" value="{{model.PortNumber || 0}}">

I assume you're using AngularJS.

我假设您正在使用 AngularJS。