这个如何实现??

Question

我就想实现增加或者删除某个用户，用这种形式

Answer 1

就是左边一个框 可能是textarea 右边也有一个,中间有>  和 < 
 比如左边的框里有几行 每行是一个用户， 选中他 然后点一下>  这个用户就被移动到到右边框里
现在我要在一个JSP页面里实现 该怎么实现呢?

Answer 2

你说的实现方式都是才用javaScript，你去找这方面的资料看看吧，

Answer 3

建两个select框id分别为“DropDownList1”，“DropDownList2”，然后利用下面脚本试试        function moveRight() {
            var source = document.getElementById("DropDownList1");
            var purpose = document.getElementById("DropDownList2");
            if (source.selectedIndex > -1) {
                var size = source.length;
                for (var i = 0;i < size; i++) {
                    if (source.options[i].selected) {
                        purpose.options.add(new Option(source[i].text,source[i].value));
                        source.options.remove(i);
                        i = i -1;
                        size = size - 1;
                    }
                }
            } else {
                alert("请选择要移动的城市！");
                return false;
            }
        }
        function moveLeft() {
            var source = document.getElementById("DropDownList2");
            var purpose = document.getElementById("DropDownList1");
            if (source.selectedIndex > -1) {
                var size = source.length;
                for (var i = 0;i < size; i++) {
                    if (source.options[i].selected) {
                        purpose.options.add(new Option(source[i].text,source[i].value));
                        source.options.remove(i);
                        i = i -1;
                        size = size - 1;
                    }
                }
            } else {
                alert("请选择要移动的城市！");
                return false;
            }
        }
        function moveUp(){
            var source = document.getElementById("DropDownList2");
            if (source.selectedIndex > -1) {
                var size = source.length;
                var tempText = "";
                var tempValue = "";
                for (var i = 0;i < size; i++) {
                    if (source.options[i].selected) {
                        //alert(source.options[i].index);
                        if (source.options[i].index != 0) {
                            tempText = source.options[i].text;
                            tempValue = source.options[i].value;
                            source.options[i].text = source.options[i-1].text;
                            source.options[i].value = source.options[i-1].value;
                            source.options[i-1].text = tempText;
                            source.options[i-1].value = tempValue;
                            source.options[i].selected = false;
                            source.options[i-1].selected = true;
                        } else {
                            alert("已经到达最上端！");
                            return false;
                        }
                    }
                }
            } else {
                alert("请选择要移动的城市！");
                return false;
            }
        }
        function moveDown(){
            var source = document.getElementById("DropDownList2");
            if (source.selectedIndex > -1) {
                var size = source.length;
                var tempText = "";
                var tempValue = "";
                for (var i = size-1;i > -1; i--) {
                    if (source.options[i].selected) {
                        //alert(source.options[i].index);
                        if (source.options[i].index != size-1) {
                            tempText = source.options[i].text;
                            tempValue = source.options[i].value;
                            source.options[i].text = source.options[i+1].text;
                            source.options[i].value = source.options[i+1].value;
                            source.options[i+1].text = tempText;
                            source.options[i+1].value = tempValue;
                            source.options[i].selected = false;
                            source.options[i+1].selected = true;
                        } else {
                            alert("已经到达最下端！");
                            return false;
                        }
                    }
                }
            } else {
                alert("请选择要移动的城市！");
                return false;
            }
        }