Javascript 从Java脚本设置时，文本区域未触发值更改事件

我试图在Java脚本预先填充的文本区域中添加一些CSS类。但是，即使在触发触发器（输入）事件之后，我仍然无法验证和设置css类

代码一直转到“值未设置”模式。当我尝试打印值时，它是空的。如何倾听值并在其中进行验证

JS:

$（文档）.ready（函数（）{
document.getElementById（'text\u area'）.value='这可以是长文本，但不是自动展开的？它应该是自动展开的。这可以是长文本，但不是自动展开的？它应该是自动展开的。这可以是长文本，但不是自动展开的？它应该是自动展开的。这可以是长文本，但不是自动展开的？它应该是自动展开的。'；
$（'textarea'）。触发器（'input'）；
$（“[autofill]”）。每个（函数（）{
警报（$（this.attr（'autofill'），this）；
if（$（this.attr（'autofill'）==“on”）{
var value=$（this）.val（）？true:false；
如果（值）{
警报（“值集”）；
}否则{
警报（“未设置值”）；
}
}
});

HTML:

文本区

JSBIN链接

---

要将值放入

textarea

元素中，请执行以下操作：

document.getElementById('text_area').value = 'This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.';

var value = $(this).val() ? true : false;

这样做：

document.getElementById('text_area').innerHTML= 'This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.';

var value = $(this).html() ? true : false;

$(document).ready(function() {

      document.getElementById('email').value = 'bala@mindlens.com.sg';
      document.getElementById('text_area1').innerHTML = '1234This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.';

      $('textarea').trigger('input');
      $('textfield').trigger('change');


      $('[autofill]').each(function() {
        console.log($(this).attr('autofill'), this);
        if ($(this).attr('autofill') == "on") {
          var value = ($(this).html() !== "") ? true : false;
          alert("value = "+$(this).html());
          console.log("value", value);
          if (value) {
            console.log("value set");alert("value set");
          } else {
            console.log("value not set");alert("value not set");
          }
        }
  });
});

并检索textarea的值，而不是此值：

document.getElementById('text_area').value = 'This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.';

var value = $(this).val() ? true : false;

这样做：

document.getElementById('text_area').innerHTML= 'This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.';

var value = $(this).html() ? true : false;

$(document).ready(function() {

      document.getElementById('email').value = 'bala@mindlens.com.sg';
      document.getElementById('text_area1').innerHTML = '1234This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.';

      $('textarea').trigger('input');
      $('textfield').trigger('change');


      $('[autofill]').each(function() {
        console.log($(this).attr('autofill'), this);
        if ($(this).attr('autofill') == "on") {
          var value = ($(this).html() !== "") ? true : false;
          alert("value = "+$(this).html());
          console.log("value", value);
          if (value) {
            console.log("value set");alert("value set");
          } else {
            console.log("value not set");alert("value not set");
          }
        }
  });
});

编辑：

document.getElementById('text_area').innerHTML= 'This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.';

var value = $(this).html() ? true : false;

$(document).ready(function() {

      document.getElementById('email').value = 'bala@mindlens.com.sg';
      document.getElementById('text_area1').innerHTML = '1234This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.';

      $('textarea').trigger('input');
      $('textfield').trigger('change');


      $('[autofill]').each(function() {
        console.log($(this).attr('autofill'), this);
        if ($(this).attr('autofill') == "on") {
          var value = ($(this).html() !== "") ? true : false;
          alert("value = "+$(this).html());
          console.log("value", value);
          if (value) {
            console.log("value set");alert("value set");
          } else {
            console.log("value not set");alert("value not set");
          }
        }
  });
});

我有。代码如下：

JS:

document.getElementById('text_area').innerHTML= 'This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.';

var value = $(this).html() ? true : false;

$(document).ready(function() {

      document.getElementById('email').value = 'bala@mindlens.com.sg';
      document.getElementById('text_area1').innerHTML = '1234This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.This can be a long text and it is not auto expanding? it shoudl auto expand.';

      $('textarea').trigger('input');
      $('textfield').trigger('change');


      $('[autofill]').each(function() {
        console.log($(this).attr('autofill'), this);
        if ($(this).attr('autofill') == "on") {
          var value = ($(this).html() !== "") ? true : false;
          alert("value = "+$(this).html());
          console.log("value", value);
          if (value) {
            console.log("value set");alert("value set");
          } else {
            console.log("value not set");alert("value not set");
          }
        }
  });
});

---

你的条件是什么？根据我的想法，Var值将始终是真的。它不应该像Var值=这个。val==一些东西吗？真：假我同意任何值，如果有任何值，我需要在css中突出显示该字段。没有效果。。它仍然没有值集。@RahulI已经编辑了你的JSBIN演示。我已经编辑了我的答案。如果您还有任何问题，请告诉我。