答案中的链接坏了，这个应该可以工作(所有的学分都转到blog.vishalon.net):

http://snipplr.com/view/5144/getset-cursor-in-html-textarea/

为了防止代码再次丢失，这里有两个主要函数:

function doGetCaretPosition(ctrl)
{
 var CaretPos = 0;

 if (ctrl.selectionStart || ctrl.selectionStart == 0)
 {// Standard.
  CaretPos = ctrl.selectionStart;
 }
 else if (document.selection)
 {// Legacy IE
  ctrl.focus ();
  var Sel = document.selection.createRange ();
  Sel.moveStart ('character', -ctrl.value.length);
  CaretPos = Sel.text.length;
 }

 return (CaretPos);
}


function setCaretPosition(ctrl,pos)
{
 if (ctrl.setSelectionRange)
 {
  ctrl.focus();
  ctrl.setSelectionRange(pos,pos);
 }
 else if (ctrl.createTextRange)
 {
  var range = ctrl.createTextRange();
  range.collapse(true);
  range.moveEnd('character', pos);
  range.moveStart('character', pos);
  range.select();
 }
}

摘自Josh Stodola的在文本框或文本区域设置键盘插入的位置用Javascript

一个泛型函数，允许您在文本框或文本区域的任何位置插入插入符号:

function setCaretPosition(elemId, caretPos) {
    var elem = document.getElementById(elemId);

    if(elem != null) {
        if(elem.createTextRange) {
            var range = elem.createTextRange();
            range.move('character', caretPos);
            range.select();
        }
        else {
            if(elem.selectionStart) {
                elem.focus();
                elem.setSelectionRange(caretPos, caretPos);
            }
            else
                elem.focus();
        }
    }
}

第一个预期参数是您希望在其上插入键盘插入符号的元素的ID。如果无法找到该元素，则什么也不会发生(显然)。第二个参数是插入符号位置索引。0会把键盘插入符号放在开头。如果传递的数字大于元素值中的字符数，则将键盘插入符放在末尾。

已在IE6及以上版本、Firefox 2、Opera 8、Netscape 9、SeaMonkey和Safari上测试。不幸的是，在Safari上，它不能与onfocus事件结合使用)。

下面是一个使用上述函数强制键盘插入符跳转到页面上所有文本区域的结尾的例子:

function addLoadEvent(func) {
    if(typeof window.onload != 'function') {
        window.onload = func;
    }
    else {
        if(func) {
            var oldLoad = window.onload;

            window.onload = function() {
                if(oldLoad)
                        oldLoad();

                func();
            }
        }
    }
}

// The setCaretPosition function belongs right here!

function setTextAreasOnFocus() {
/***
 * This function will force the keyboard caret to be positioned
 * at the end of all textareas when they receive focus.
 */
    var textAreas = document.getElementsByTagName('textarea');

    for(var i = 0; i < textAreas.length; i++) {
        textAreas[i].onfocus = function() {
            setCaretPosition(this.id, this.value.length);
        }
    }

    textAreas = null;
}

addLoadEvent(setTextAreasOnFocus);

HTMLInputElement。临时人选;

// References
var e = document.getElementById( "helloworldinput" );

// Move caret to beginning on focus
e.addEventListener( "focus", function( event )
{
    // References
    var e = event.target;

    // Action
    e.setSelectionRange( 0, 0 );            // Doesn’t work for focus event
    
    window.setTimeout( function()
    {
        e.setSelectionRange( 0, 0 );        // Works
        //e.setSelectionRange( 1, 1 );      // Move caret to second position
        //e.setSelectionRange( 1, 2 );      // Select second character

    }, 0 );

}, false );

浏览器兼容性(仅适用于文本、搜索、url、电话和密码类型): https://developer.mozilla.org/en-US/docs/Web/API/HTMLInputElement/setSelectionRange#Specifications

我将修复如下条件:

function setCaretPosition(elemId, caretPos)
{
 var elem = document.getElementById(elemId);
 if (elem)
 {
  if (typeof elem.createTextRange != 'undefined')
  {
   var range = elem.createTextRange();
   range.move('character', caretPos);
   range.select();
  }
  else
  {
   if (typeof elem.selectionStart != 'undefined')
    elem.selectionStart = caretPos;
   elem.focus();
  }
 }
}

答案中的链接坏了，这个应该可以工作(所有的学分都转到blog.vishalon.net):

http://snipplr.com/view/5144/getset-cursor-in-html-textarea/

为了防止代码再次丢失，这里有两个主要函数:

function doGetCaretPosition(ctrl)
{
 var CaretPos = 0;

 if (ctrl.selectionStart || ctrl.selectionStart == 0)
 {// Standard.
  CaretPos = ctrl.selectionStart;
 }
 else if (document.selection)
 {// Legacy IE
  ctrl.focus ();
  var Sel = document.selection.createRange ();
  Sel.moveStart ('character', -ctrl.value.length);
  CaretPos = Sel.text.length;
 }

 return (CaretPos);
}


function setCaretPosition(ctrl,pos)
{
 if (ctrl.setSelectionRange)
 {
  ctrl.focus();
  ctrl.setSelectionRange(pos,pos);
 }
 else if (ctrl.createTextRange)
 {
  var range = ctrl.createTextRange();
  range.collapse(true);
  range.moveEnd('character', pos);
  range.moveStart('character', pos);
  range.select();
 }
}

function SetCaretEnd(tID) {
    tID += "";
    if (!tID.startsWith("#")) { tID = "#" + tID; }
    $(tID).focus();
    var t = $(tID).val();
    if (t.length == 0) { return; }
    $(tID).val("");
    $(tID).val(t);
    $(tID).scrollTop($(tID)[0].scrollHeight); }