如何将光标移动到可用实体的结尾

Question

我需要将插入符号移动到contenteditable节点的末尾，就像在Gmail便笺小部件上一样。

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

Answer 1

也有另一种问题。

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

例如，如果div包含其他div，并且这些其他div包含其他内容，则可能会发生一些问题。

为了解决这些问题，我已经安排了以下解决方案，这是一个改善Nico的一个：

//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); 

这种方式，游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语句还应该考虑所有其他不能包含文本的标签。这些元素被命名为void元素，并且在this question中有一些关于如何测试元素是否为空的方法。因此，假设存在一个名为canContainText函数，返回true如果参数不是一个空元素，下面的代码行：

canContainText(getLastChildElement(contentEditableElement)) 

EDIT＃2：

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

应替换：上面的代码是完全更新的，每个变化描述和讨论

Answer 2

Geowa4的解决方案将适用于textarea，但不适用于contenteditable元素。

该解决方案用于将插入符号移动到contenteditable元素的末尾。它应该支持所有支持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 
    } 
} 

它可通过类似于代码使用：

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

Answer 3

可以将光标设置到范围末端：

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; 
}