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

因为我确实需要这个解决方案，而典型的基线解决方案(聚焦输入-然后设置值等于本身)不能跨浏览器工作，所以我花了一些时间调整和编辑所有内容以使其工作。在@kd7的代码的基础上，这里是我想出的。

享受吧!适用于IE6+， Firefox, Chrome, Safari, Opera

跨浏览器插入符号定位技术(例如:将光标移动到END)

// ** USEAGE ** (returns a boolean true/false if it worked or not)
// Parameters ( Id_of_element, caretPosition_you_want)

setCaretPosition('IDHERE', 10); // example

肉和土豆基本上是@kd7的setCaretPosition，最大的调整是if (el。selectionStart || el。selectionStart === 0)，在firefox中selectionStart是从0开始的，在布尔中当然是变为False，所以它在这里中断了。

在chrome最大的问题是，只是给它.focus()是不够的(它一直选择所有的文本!)因此，我们将自身的值设为el。Value = el.value;在调用我们的函数之前，现在它有一个抓取&位置的输入使用selectionStart。

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

    el.value = el.value;
    // ^ this is used to not only get "focus", but
    // to make sure we don't have it everything -selected-
    // (it causes an issue in chrome, and having it doesn't hurt any other browser)

    if (el !== null) {

        if (el.createTextRange) {
            var range = el.createTextRange();
            range.move('character', caretPos);
            range.select();
            return true;
        }

        else {
            // (el.selectionStart === 0 added for Firefox bug)
            if (el.selectionStart || el.selectionStart === 0) {
                el.focus();
                el.setSelectionRange(caretPos, caretPos);
                return true;
            }

            else  { // fail city, fortunately this never happens (as far as I've tested) :)
                el.focus();
                return false;
            }
        }
    }
}

我发现了一个简单的方法来解决这个问题，在IE和Chrome测试:

function setCaret(elemId, caret)
 {
   var elem = document.getElementById(elemId);
   elem.setSelectionRange(caret, caret);
 }

将文本框id和插入符号位置传递给此函数。

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();
 }
}

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

我稍微调整了kd7的答案，因为elem。当selectionStart恰好为0时，selectionStart将计算为false。

function setCaretPosition(elem, caretPos) {
    var range;

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