如何将光标移动到可信实体的末尾

时间:2009-07-14 13:13:26

标签: javascript contenteditable cursor-position

我需要将插入符号移到contenteditable节点的末尾,就像在Gmail备注小部件上一样。

我在StackOverflow上读取了线程,但这些解决方案基于使用输入,它们不适用于contenteditable元素。

7 个答案:

答案 0 :(得分:207)

Geowa4的解决方案适用于textarea,但不适用于满足要求的元素。

此解决方案用于将插入符号移动到可满足元素的末尾。它应该适用于所有支持contenteditable的浏览器。

function setEndOfContenteditable(contentEditableElement)
{
    var range,selection;
    if(document.createRange)//Firefox, Chrome, Opera, Safari, IE 9+
    {
        range = document.createRange();//Create a range (a range is a like the selection but invisible)
        range.selectNodeContents(contentEditableElement);//Select the entire contents of the element with the range
        range.collapse(false);//collapse the range to the end point. false means collapse to end rather than the start
        selection = window.getSelection();//get the selection object (allows you to change selection)
        selection.removeAllRanges();//remove any selections already made
        selection.addRange(range);//make the range you have just created the visible selection
    }
    else if(document.selection)//IE 8 and lower
    { 
        range = document.body.createTextRange();//Create a range (a range is a like the selection but invisible)
        range.moveToElementText(contentEditableElement);//Select the entire contents of the element with the range
        range.collapse(false);//collapse the range to the end point. false means collapse to end rather than the start
        range.select();//Select the range (make it the visible selection
    }
}

它可以被类似的代码使用:

elem = document.getElementById('txt1');//This is the element that you want to move the caret to the end of
setEndOfContenteditable(elem);

答案 1 :(得分:22)

还有另一个问题。

如果contenteditable div不包含其他多行元素,则Nico Burns的解决方案有效。

例如,如果一个div包含其他div,并且这些其他div包含其他内容,则可能会出现一些问题。

为了解决这些问题,我安排了以下解决方案,即Nico的改进:

//Namespace management idea from http://enterprisejquery.com/2010/10/how-good-c-habits-can-encourage-bad-javascript-habits-part-1/
(function( cursorManager ) {

    //From: http://www.w3.org/TR/html-markup/syntax.html#syntax-elements
    var voidNodeTags = ['AREA', 'BASE', 'BR', 'COL', 'EMBED', 'HR', 'IMG', 'INPUT', 'KEYGEN', 'LINK', 'MENUITEM', 'META', 'PARAM', 'SOURCE', 'TRACK', 'WBR', 'BASEFONT', 'BGSOUND', 'FRAME', 'ISINDEX'];

    //From: https://stackoverflow.com/questions/237104/array-containsobj-in-javascript
    Array.prototype.contains = function(obj) {
        var i = this.length;
        while (i--) {
            if (this[i] === obj) {
                return true;
            }
        }
        return false;
    }

    //Basic idea from: https://stackoverflow.com/questions/19790442/test-if-an-element-can-contain-text
    function canContainText(node) {
        if(node.nodeType == 1) { //is an element node
            return !voidNodeTags.contains(node.nodeName);
        } else { //is not an element node
            return false;
        }
    };

    function getLastChildElement(el){
        var lc = el.lastChild;
        while(lc && lc.nodeType != 1) {
            if(lc.previousSibling)
                lc = lc.previousSibling;
            else
                break;
        }
        return lc;
    }

    //Based on Nico Burns's answer
    cursorManager.setEndOfContenteditable = function(contentEditableElement)
    {

        while(getLastChildElement(contentEditableElement) &&
              canContainText(getLastChildElement(contentEditableElement))) {
            contentEditableElement = getLastChildElement(contentEditableElement);
        }

        var range,selection;
        if(document.createRange)//Firefox, Chrome, Opera, Safari, IE 9+
        {    
            range = document.createRange();//Create a range (a range is a like the selection but invisible)
            range.selectNodeContents(contentEditableElement);//Select the entire contents of the element with the range
            range.collapse(false);//collapse the range to the end point. false means collapse to end rather than the start
            selection = window.getSelection();//get the selection object (allows you to change selection)
            selection.removeAllRanges();//remove any selections already made
            selection.addRange(range);//make the range you have just created the visible selection
        }
        else if(document.selection)//IE 8 and lower
        { 
            range = document.body.createTextRange();//Create a range (a range is a like the selection but invisible)
            range.moveToElementText(contentEditableElement);//Select the entire contents of the element with the range
            range.collapse(false);//collapse the range to the end point. false means collapse to end rather than the start
            range.select();//Select the range (make it the visible selection
        }
    }

}( window.cursorManager = window.cursorManager || {}));

用法:

var editableDiv = document.getElementById("my_contentEditableDiv");
cursorManager.setEndOfContenteditable(editableDiv);

通过这种方式,光标肯定位于最后一个元素的末尾,最终嵌套。

编辑#1 :为了更通用,while语句还应考虑所有其他不能包含文本的标记。这些元素名为 void elements ,在this question中有一些方法可以测试元素是否为void。因此,假设存在一个名为canContainText的函数,如果参数不是void元素,则返回true,代码如下:

contentEditableElement.lastChild.tagName.toLowerCase() != 'br'

应替换为:

canContainText(getLastChildElement(contentEditableElement))

编辑#2 :上述代码已完全更新,并描述和讨论了所有更改

答案 2 :(得分:3)

可以通过范围将光标设置到最后:

setCaretToEnd(target/*: HTMLDivElement*/) {
  const range = document.createRange();
  const sel = window.getSelection();
  range.selectNodeContents(target);
  range.collapse(false);
  sel.removeAllRanges();
  sel.addRange(range);
  target.focus();
  range.detach(); // optimization

  // set scroll to the end if multiline
  target.scrollTop = target.scrollHeight; 
}

答案 3 :(得分:1)

如果您不关心较旧的浏览器,那么这个就对我有用。

// [optional] make sure focus is on the element
yourContentEditableElement.focus();
// select all the content in the element
document.execCommand('selectAll', false, null);
// collapse selection to the end
document.getSelection().collapseToEnd();

答案 4 :(得分:0)

我在尝试使元素可编辑时遇到类似的问题。在Chrome和FireFox中可能出现这种情况,但在FireFox中,插入号要么移至输入的开头,要么移至输入结束后的一个空格。我认为最终用户在尝试编辑内容时非常困惑。

我找不到尝试几种方法的解决方案。唯一对我有用的方法是,通过在我的我的内部放置普通的旧文本输入来“解决问题”。现在可以了。似乎“内容可编辑”仍然是最前沿的技术,取决于上下文,该技术可能会或可能不会像您希望的那样起作用。

答案 5 :(得分:0)

将光标移动到可编辑跨度的末尾以响应焦点事件:

  moveCursorToEnd(el){
    if(el.innerText && document.createRange)
    {
      window.setTimeout(() =>
        {
          let selection = document.getSelection();
          let range = document.createRange();

          range.setStart(el.childNodes[0],el.innerText.length);
          range.collapse(true);
          selection.removeAllRanges();
          selection.addRange(range);
        }
      ,1);
    }
  }

并在事件处理程序中调用它(在此处反应):

onFocus={(e) => this.moveCursorToEnd(e.target)}} 

答案 6 :(得分:0)

最初开始输入时,contenteditable <div><span>的问题已解决。一种解决方法是在div元素和该函数上触发焦点事件,清除并重新填充div元素中已有的内容。这样,问题得以解决,最后您可以使用范围和选择将光标放置在末尾。为我工作。

  moveCursorToEnd(e : any) {
    let placeholderText = e.target.innerText;
    e.target.innerText = '';
    e.target.innerText = placeholderText;

    if(e.target.innerText && document.createRange)
    {
      let range = document.createRange();
      let selection = window.getSelection();
      range.selectNodeContents(e.target);
      range.setStart(e.target.firstChild,e.target.innerText.length);
      range.setEnd(e.target.firstChild,e.target.innerText.length);
      selection.removeAllRanges();
      selection.addRange(range);
    }
  }

在HTML代码中:

<div contentEditable="true" (focus)="moveCursorToEnd($event)"></div>