Question

我不知道如何很好地解释它，但是我正在尝试构建一个文本自动扩展的文本区域，但是我发现的所有示例，文本区域都向下增长，我希望文本区域向上增长

示例：

var observe;
if (window.attachEvent) {
  observe = function(element, event, handler) {
    element.attachEvent('on' + event, handler);
  };
} else {
  observe = function(element, event, handler) {
    element.addEventListener(event, handler, false);
  };
}

function init() {
  var text = document.getElementById('text');

  function resize() {
    text.style.height = 'auto';
    text.style.height = text.scrollHeight + 'px';
  }
  /* 0-timeout to get the already changed text */
  function delayedResize() {
    window.setTimeout(resize, 0);
  }
  observe(text, 'change', resize);
  observe(text, 'cut', delayedResize);
  observe(text, 'paste', delayedResize);
  observe(text, 'drop', delayedResize);
  observe(text, 'keydown', delayedResize);

  text.focus();
  text.select();
  resize();
}

textarea {
  border: 0 none white;
  overflow: hidden;
  padding: 0;
  outline: none;
  background-color: #D0D0D0;
  resize: none;
}

<body onload="init();">
  <textarea rows="1" style="height:1em;" id="text"></textarea>
</body>

http://jsfiddle.net/0a9u7h2g/2/

如何更改此代码以实现此目的？

Answer 1

我假设您是说它应该向上增长，而不是向下增长。通过将MainClass放在其包含元素的底部，它将被迫向上增长。

class SuperClass(MainClass):
    def __init__(self):
        super().__init__()
        self._index = 0

    @property
    def index(self):
        return self._index

    @index.setter
    def index(self, value):
        self._index = value

textarea

var observe;
if (window.attachEvent) {
  observe = function(element, event, handler) {
    element.attachEvent('on' + event, handler);
  };
} else {
  observe = function(element, event, handler) {
    element.addEventListener(event, handler, false);
  };
}

function init() {
  var text = document.getElementById('text');

  function resize() {
    text.style.height = 'auto';
    text.style.height = text.scrollHeight + 'px';
  }
  /* 0-timeout to get the already changed text */
  function delayedResize() {
    window.setTimeout(resize, 0);
  }
  observe(text, 'change', resize);
  observe(text, 'cut', delayedResize);
  observe(text, 'paste', delayedResize);
  observe(text, 'drop', delayedResize);
  observe(text, 'keydown', delayedResize);

  text.focus();
  text.select();
  resize();
}

自动将文本区域向北扩展

1 个答案: