在 contentEditable <div> 上设置光标位置

Question

当 contentEditable='on'

重新获得焦点时，我正在寻求一个明确的跨浏览器解决方案，将光标/插入符号位置设置为最后一个已知位置。似乎内容可编辑 div 的默认功能是每次单击时将插入符号/光标移动到 div 中文本的开头，这是不可取的。

我相信当他们离开 div 的焦点时我必须将当前光标位置存储在一个变量中，然后当他们再次将焦点放在里面时重新设置它，但我无法将它们放在一起，或者找到一个可以工作的代码示例。

如果有人有任何想法、工作代码 sn-ps 或示例，我很乐意看到它们。

我还没有任何代码，但这是我所拥有的：

<script type="text/javascript">
// jQuery
$(document).ready(function() {
   $('#area').focus(function() { .. }  // focus I would imagine I need.
}
</script>
<div id="area" contentEditable="true"></div>

PS。我已经尝试过这个资源，但它似乎不适用于

。也许只适用于 textarea (How to move cursor to end of contenteditable entity)

【问题讨论】：

• 我不知道 contentEditable 在非 IE 浏览器中工作过 o_o
• 是的 aditya。
• aditya, Safari 2+, Firefox 3+ 我想。
• 尝试在 div 上设置 tabindex="0"。这应该使它在大多数浏览器中都具有焦点。

Answer 1

这与基于标准的浏览器兼容，但在 IE 中可能会失败。我提供它作为一个起点。 IE 不支持 DOM Range。

var editable = document.getElementById('editable'),
    selection, range;

// Populates selection and range variables
var captureSelection = function(e) {
    // Don't capture selection outside editable region
    var isOrContainsAnchor = false,
        isOrContainsFocus = false,
        sel = window.getSelection(),
        parentAnchor = sel.anchorNode,
        parentFocus = sel.focusNode;

    while(parentAnchor && parentAnchor != document.documentElement) {
        if(parentAnchor == editable) {
            isOrContainsAnchor = true;
        }
        parentAnchor = parentAnchor.parentNode;
    }

    while(parentFocus && parentFocus != document.documentElement) {
        if(parentFocus == editable) {
            isOrContainsFocus = true;
        }
        parentFocus = parentFocus.parentNode;
    }

    if(!isOrContainsAnchor || !isOrContainsFocus) {
        return;
    }

    selection = window.getSelection();

    // Get range (standards)
    if(selection.getRangeAt !== undefined) {
        range = selection.getRangeAt(0);

    // Get range (Safari 2)
    } else if(
        document.createRange &&
        selection.anchorNode &&
        selection.anchorOffset &&
        selection.focusNode &&
        selection.focusOffset
    ) {
        range = document.createRange();
        range.setStart(selection.anchorNode, selection.anchorOffset);
        range.setEnd(selection.focusNode, selection.focusOffset);
    } else {
        // Failure here, not handled by the rest of the script.
        // Probably IE or some older browser
    }
};

// Recalculate selection while typing
editable.onkeyup = captureSelection;

// Recalculate selection after clicking/drag-selecting
editable.onmousedown = function(e) {
    editable.className = editable.className + ' selecting';
};
document.onmouseup = function(e) {
    if(editable.className.match(/\sselecting(\s|$)/)) {
        editable.className = editable.className.replace(/ selecting(\s|$)/, '');
        captureSelection();
    }
};

editable.onblur = function(e) {
    var cursorStart = document.createElement('span'),
        collapsed = !!range.collapsed;

    cursorStart.id = 'cursorStart';
    cursorStart.appendChild(document.createTextNode('—'));

    // Insert beginning cursor marker
    range.insertNode(cursorStart);

    // Insert end cursor marker if any text is selected
    if(!collapsed) {
        var cursorEnd = document.createElement('span');
        cursorEnd.id = 'cursorEnd';
        range.collapse();
        range.insertNode(cursorEnd);
    }
};

// Add callbacks to afterFocus to be called after cursor is replaced
// if you like, this would be useful for styling buttons and so on
var afterFocus = [];
editable.onfocus = function(e) {
    // Slight delay will avoid the initial selection
    // (at start or of contents depending on browser) being mistaken
    setTimeout(function() {
        var cursorStart = document.getElementById('cursorStart'),
            cursorEnd = document.getElementById('cursorEnd');

        // Don't do anything if user is creating a new selection
        if(editable.className.match(/\sselecting(\s|$)/)) {
            if(cursorStart) {
                cursorStart.parentNode.removeChild(cursorStart);
            }
            if(cursorEnd) {
                cursorEnd.parentNode.removeChild(cursorEnd);
            }
        } else if(cursorStart) {
            captureSelection();
            var range = document.createRange();

            if(cursorEnd) {
                range.setStartAfter(cursorStart);
                range.setEndBefore(cursorEnd);

                // Delete cursor markers
                cursorStart.parentNode.removeChild(cursorStart);
                cursorEnd.parentNode.removeChild(cursorEnd);

                // Select range
                selection.removeAllRanges();
                selection.addRange(range);
            } else {
                range.selectNode(cursorStart);

                // Select range
                selection.removeAllRanges();
                selection.addRange(range);

                // Delete cursor marker
                document.execCommand('delete', false, null);
            }
        }

        // Call callbacks here
        for(var i = 0; i < afterFocus.length; i++) {
            afterFocus[i]();
        }
        afterFocus = [];

        // Register selection again
        captureSelection();
    }, 10);
};