jQuery插件，将内容插入到光标处

(function ($) {
    $.fn.extend({
        insertAtCaret : function (myValue) {
            var $t = $(this)[0];
            if (document.selection) {
                this.focus();
                sel = document.selection.createRange();
                sel.text = myValue;
                this.focus();
            } else
                if ($t.selectionStart || $t.selectionStart == '0') {
                    var startPos = $t.selectionStart;
                    var endPos = $t.selectionEnd;
                    var scrollTop = $t.scrollTop;
                    $t.value = $t.value.substring(0, startPos) + myValue + $t.value.substring(endPos, $t.value.length);
                    this.focus();
                    $t.selectionStart = startPos + myValue.length;
                    $t.selectionEnd = startPos + myValue.length;
                    $t.scrollTop = scrollTop;
                } else {
                    this.value += myValue;
                    this.focus();
                }
        }
    })
})(jQuery);

//调用方法：
$("select").insertAtCaret();

应用案例

<!DOCTYPE html>
<html>
<head>
    <title>无标题页</title>

    <script type="text/javascript" src="http://sy.zgsapt.com/js/jquery-1.7.2.min.js"></script>

    <script type="text/javascript">
        (function ($) {
            $.fn.extend({
                insertAtCaret: function (myValue) {
                    var $t = $(this)[0];
                    if (document.selection) {
                        this.focus();
                        sel = document.selection.createRange();
                        sel.text = myValue;
                        this.focus();
                    } else
                        if ($t.selectionStart || $t.selectionStart == '0') {
                            var startPos = $t.selectionStart;
                            var endPos = $t.selectionEnd;
                            var scrollTop = $t.scrollTop;
                            $t.value = $t.value.substring(0, startPos) + myValue + $t.value.substring(endPos, $t.value.length);
                            this.focus();
                            $t.selectionStart = startPos + myValue.length;
                            $t.selectionEnd = startPos + myValue.length;
                            $t.scrollTop = scrollTop;
                        } else {
                            this.value += myValue;
                            this.focus();
                        }
                }
            })
        })(jQuery);

        $(document).ready(function () {
            $("#numd").bind("mouseleave", function () {
                document.getElementById('keybored').style.display = 'none';
                document.getElementById('Nm').blur();
            });

            $("#Nm").focus(function () {
                document.getElementById('keybored').style.display = '';
            });
            $(".readbtns").click(function () {
                $("#Nm").insertAtCaret($(this).val());

            });

        });

    </script>

</head>
<body>
    <ul>
        <li>
            <input />
            <div>
            </div>
        </li>
    </ul>
    <input id="hid" type="text" value="" style="display: none" />
    <span id="numd" style="border: 1px solid red; clear: both; display: inline-block; font: 800em;">
        <input type="text" id="Nm" name="Nm" value="" />
        <div style="display: none; border: 1px solid #A2B4C6;  150px; height: 400px;"
            id="keybored">
            <input type="button" class="readbtns" value="1" />
            <input type="button" class="readbtns" value="2" />
            <input type="button" class="readbtns" value="3" />
            <input type="button" class="readbtns" value="4" />
            <input type="button" class="readbtns" value="5" />
            <input type="button" class="readbtns" value="6" />
            <input type="button" class="readbtns" value="7" />
            <input type="button" class="readbtns" value="8" />
            <input type="button" class="readbtns" value="9" />
        </div>
    </span>
</body>
</html>

相关阅读:
游戏开发系统功能（9）
游戏开发创建游戏世界（8）
游戏开发沟通和开会技巧（7）
游戏开发策划工作（6）
游戏开发了解测试工作（4）
Django：学习笔记(9)——用户身份认证
 Django：学习笔记(8)——视图
 Django：学习笔记(7)——模型进阶
 Django：学习笔记(6)——模型
 Django：学习笔记(5)——会话
原文地址：https://www.cnblogs.com/yeminglong/p/3914386.html