Jquery easyui datagrid每次切换下一页丢失上一页的记录，最后保存数据错乱的问题

1、实例化两个数组

 var idsArray = new Array();    //记录勾选的id
 var UnidsArray = new Array();   //记录取消勾选的id

j's代码如下：

function loadingDatagridCheckNew(url, columns, thisid, bol) {
    var _thid = "ID";
    if (thisid != null) {
        _thid = thisid;
    }
    var bv = true;
    if (bol != null) {
        bv = bol;
    }
    $('#magazineGrid').datagrid({
        height: $(window).height() - $('fieldset').height() - 50,
        width: 'auto',
        url: url,//地址
        method: 'POST',
        queryParams: queryParams,
        idField: _thid,
        striped: true,
        fitColumns: false,// true,//宽度自适应
        singleSelect: bv,
        rownumbers: true,
        pagination: true,
        nowrap: true,// false,//允许换行
        emptyMsg: '无记录',
        loadMsg: '正在加载中，请稍等... ',
        pageSize: 20,
        pageList: [10, 20, 50, 100, 150, 200],
        showFooter: true,
        columns: columns,
        selectOnCheck: true,
        checkOnSelect: true,
        toolbar: '#datagrid-toolbar',
        onBeforeLoad: function (param) {
            addSelectedGoodsIdToArray();
        },
        onLoadSuccess: function (data) {
            if ($(".easyui-tooltip")) {
                $(".easyui-tooltip").tooltip({
                    position: 'left'
                });
            }
            if (data) {
                $.each(data.rows, function (index, item) {
                    if (item.Checked) { //数据库记录勾选的字段，加载的时候自动绑定
                        if (!UnidsArray.includes(item.SST_ID)) {
                            $('#magazineGrid').datagrid('checkRow', index);
                        }
                    }
                });
            }
            var rowsData = data.rows;
            if (idsArray.length != 0) {
               // $.each(idsArray, function (i, e) {
                for (var index = 0; index < rowsData.length; index++) {
                    if (idsArray.includes(rowsData[index].SST_ID)) {
                            $('#magazineGrid').datagrid('selectRow', index);
                    } else {
                        if (UnidsArray.includes(rowsData[index].SST_ID)) {
                             $('#magazineGrid').datagrid('unselectRow', index);
                           } 
                        }
                    }
               // });
            }
        },
        onUncheck: function (rowIndex, rowData) {
            if (idsArray.length == 0) {
                UnidsArray.push(rowData["SST_ID"]);
            } else {
                for (var index = 0; index < idsArray.length; index++) {
                    if (idsArray[index] == rowData["SST_ID"]) {
                        removeArrayValue(idsArray, rowData["SST_ID"]);
                        break;
                    }
                }
            }
        },
        onCheck: function (rowIndex, rowData) {
            if (idsArray.length == 0) {
                idsArray.push(rowData["SST_ID"]);
            } else {
                for (var index = 0; index < idsArray.length; index++) {
                    if (idsArray[index] == rowData["SST_ID"]) {
                        break;
                    }
                    if (index == idsArray.length - 1) {
                        idsArray.push(rowData["SST_ID"]);
                        break;
                    }
                }
            } 
        },
        onSelectAll: function (rows) {
            if (idsArray.length == 0) {
                $.each(rows, function (index, item) {
                    idsArray.push(item["SST_ID"]);
                });
            }
            else {
                $.each(rows, function (index, item) {
                    for (var index = 0; index < idsArray.length; index++) {
                        if (idsArray[index] == item["SST_ID"]) {
                            break;
                        }
                        if (index == idsArray.length - 1) {
                            idsArray.push(item["SST_ID"]);
                            break;
                        }
                    }
                });
            }
        },
        //onUnselectAll: function (rows) {
        //    alert('onUnselectAll');
        //},
        //onCheckAll: function (rows) {
        //    alert("onCheckAll");
        //},
        onUncheckAll: function (rows) {
            if (idsArray.length == 0) {
                $.each(rows, function (index, item) {
                    UnidsArray.push(item["SST_ID"]);
                });
            }
            else {
                $.each(rows, function (index, item) {
                    for (var i = 0; i < idsArray.length; i++) {
                        if (idsArray[i] == item["SST_ID"]) {
                            removeArrayValue(idsArray, item["SST_ID"]);
                            break;
                        }
                    }
                });
            }
        }

    });
}


function addSelectedGoodsIdToArray() {
    var rows = $('#magazineGrid').datagrid('getSelections');
    if (rows.length > 0) {
        $.each(rows, function (i, row) {
            if (idsArray.length == 0) {
                if (UnidsArray.indexOf(row["SST_ID"]) == -1) {
                    idsArray.push(row["SST_ID"]);
                }
            } else {
                for (var index = 0; index < idsArray.length; index++) {
                    if (idsArray[index] == row["SST_ID"]) {
                        break;
                    }
                    if (index == idsArray.length - 1) {
                        if (UnidsArray.indexOf(row["SST_ID"]) == -1) {
                            idsArray.push(row["SST_ID"]);
                        }
                        break;
                    }
                }
            }
        });
    }
}

function removeSelectedGoodsIdToArray(rows) {
    //var rows = $dg.datagrid('getSelections');
    if (rows.length > 0) {
        $.each(rows, function (i, row) {
            if (idsArray.length > 0) {
                for (var index = 0; index < idsArray.length; index++) {
                    removeArrayValue(idsArray, row["SST_ID"]);
                }
            }
        });
    }
}

function removeArrayValue(arr, val) {
    for (var i = 0; i < arr.length; i++) {
        if (arr[i] == val) {
            arr.splice(i, 1);
            UnidsArray.push(val);
            break;
        }
    }
}

保存的时候只取idsArray这是勾选的数组，UnidsArray这是不勾选的数组传到后台，后台业务先把取消的从数据库删除了，然后再存勾选的。