挂起脏数据与恢复脏数据

SpreadJS允许用户通过标记单元格的脏状态来获取表单中已变更的单元格值的详细信息。 此选项提供有关单元格修改的信息，但也会引起很多性能开销，尤其是当用户需要对批量数据执行排序操作时。

为了进行性能调整，建议使用 suspendDirty 方法和 resumeDirty 方法。

suspendDirty方法停止SpreadJS在单元格中标记脏状态，直到排序完成为止，resumeDirty方法允许您在需要时还原单元格的脏状态。 这两种方法都在很大程度上提高了性能。

请参考以下代码片段，以使用 suspendDirty 方法和 resumeDirty 方法，以便在使用SpreadJS时提高性能。

var startTime, endTime;
window.onload = function () {
var spread = new GC.Spread.Sheets.Workbook(document.getElementById("ss"));
var sheet = spread.getActiveSheet();
var data = generateData(50000);
var colInfos = generateBindingColumnInfos(7);
loadingData(sheet, colInfos, data);
spread.bind(GC.Spread.Sheets.Events.RangeSorting, function (sneder, args) {
// 调用suspendDirty（）方法停止标记排序的单元格变脏数据
sheet.suspendDirty();
});
spread.bind(GC.Spread.Sheets.Events.RangeSorted, function (sender, args) {
// 调用resumeDirty（）方法以还原单元格的脏数据状态
sheet.resumeDirty();
});
};
function loadingData(sheet, colInfos, data)
{
sheet.suspendPaint();
sheet.autoGenerateColumns = false;
sheet.bindColumns(colInfos);
sheet.setDataSource(data);
sheet.rowFilter(new GC.Spread.Sheets.Filter.HideRowFilter(new GC.Spread.Sheets.Range(0, 0, sheet.getRowCount(), sheet.getColumnCount())));
sheet.resumePaint();
}
function generateData(itemCount) {
var data = [];
var countries = ["China", "American", "UK", "Japan", "France"];
var products = ["Computer", "Car", "Others"];
var colors = ["Red", "Green", "Blue", "White", "Black", "Yellow", "Pink", "Orange"];
var dt = new Date();
for (var i = 0; i < itemCount; i++)
{
var item =
{
id: i,
date: new Date(dt.getFullYear(), i % 12, 1),
country: countries[Math.floor(Math.random() * countries.length)],
product: products[Math.floor(Math.random() * products.length)],
color: colors[Math.floor(Math.random() * colors.length)],
amount: 1000 + Math.random() * 10000,
big: Math.random() > .5
};
data.push(item);
}
return data;
}
function generateBindingColumnInfos(colCount) {
var bindColumnInfos = [
{ name: "id", displayName: "ID", size: 60 },
{ name: "product", displayName: "Product", size: 90 },
{ name: "country", displayName: "Country", size: 90 },
{ name: "amount", displayName: "Amount", size: 90, formatter: "#,##0" },
{ name: "date", displayName: "Date", size: 90, formatter: 'yyyy-mm-dd' },
{ name: "color", displayName: "Color", size: 85 },
{ name: "big", displayName: "Big", size: 90, cellType: new GC.Spread.Sheets.CellTypes.CheckBox() }
];
return bindColumnInfos;
}