检查文本框是否有空值。

I have the following code:

我有以下代码:

var inp = $("#txt");

if(inp.val() != "")
// do something

Is there any other way to check for empty textbox using the variable 'inp'

是否有其他方法使用变量“inp”检查空文本框

8 个解决方案

#1

if (inp.val().length > 0) {
    // do something
}

if you want anything more complicated, consider regex or use the validation plugin which takes care of this for you

如果您想要更复杂的东西，可以考虑使用regex或使用验证插件来为您解决这个问题

#2

var inp = $("#txt").val();
if(jQuery.trim(inp).length > 0)
{
   //do something
}

Removes white space before checking. If the user entered only spaces then this will still work.

在检查前删除空白。如果用户只输入空格，那么这仍然有效。

#3

if ( $("#txt").val().length > 0 )
{
  // do something
}

Your method fails when there is more than 1 space character inside the textbox.

当文本框中有超过一个空格字符时，您的方法将失败。

#4

$('input:text').filter(function() { return this.value.length > 0; });

#5

Use the following to check if text box is empty or have more than 1 white spaces

使用以下命令检查文本框是否为空或有超过1个空格

var name = jQuery.trim($("#ContactUsName").val());

if ((name.length == 0))
{
    Your code 
}
else
{
    Your code
}

#6

if ( $("#txt").val().length == 0 )
{
  // do something
}

I had to add in the == to get it to work for me, otherwise it ignored the condition even with empty text input. May help someone.

我必须添加==才能让它为我工作，否则即使是空文本输入，它也会忽略条件。可以帮助别人。

#7

Also You can use

你也可以使用

$value = $("#txt").val();

if($value == "")
{
    //Your Code Here
}
else
{
   //Your code
}

Try it. It work.

试一试。它的工作。

#8

The check can be done like this:

支票可以这样做:

if (!!inp.val()) {

}

and even shorter:

甚至更短:

if (inp.val()) {

}