使用Ext可以说最多的就是Grid了，它可以方便的展示列表数据并能够对数据分页和排序。
下面从最简单Grid例子开始――《Basic Array Grid》。
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上截图和代码（这个例子也可以在Ext官方的例程列表中找到）
/*!
* Ext JS Library 3.2.1
* Copyright(c) 2006-2010 Ext JS, Inc.
* licensing@extjs.com
* http://www.extjs.com/license
*/
Ext.onReady(function(){
// NOTE: This is an example showing simple state management. During development,
// it is generally best to disable state management as dynamically-generated ids
// can change across page loads, leading to unpredictable results. The developer
// should ensure that stable state ids are set for stateful components in real apps.
Ext.state.Manager.setProvider(new Ext.state.CookieProvider());
// sample static data for the store
var myData = [
['3m Co',71.72,0.02,0.03,'9/1 12:00am'],
['Alcoa Inc',29.01,0.42,1.47,'9/1 12:00am'],
['Altria Group Inc',83.81,0.28,0.34,'9/1 12:00am'],
['American Express Company',52.55,0.01,0.02,'9/1 12:00am'],
['American International Group, Inc.',64.13,0.31,0.49,'9/1 12:00am'],
['AT&T Inc.',31.61,-0.48,-1.54,'9/1 12:00am'],
['Boeing Co.',75.43,0.53,0.71,'9/1 12:00am'],
['Caterpillar Inc.',67.27,0.92,1.39,'9/1 12:00am'],
['Citigroup, Inc.',49.37,0.02,0.04,'9/1 12:00am'],
['E.I. du Pont de Nemours and Company',40.48,0.51,1.28,'9/1 12:00am'],
['Exxon Mobil Corp',68.1,-0.43,-0.64,'9/1 12:00am'],
['General Electric Company',34.14,-0.08,-0.23,'9/1 12:00am'],
['General Motors Corporation',30.27,1.09,3.74,'9/1 12:00am'],
['Hewlett-Packard Co.',36.53,-0.03,-0.08,'9/1 12:00am'],
['Honeywell Intl Inc',38.77,0.05,0.13,'9/1 12:00am'],
['Intel Corporation',19.88,0.31,1.58,'9/1 12:00am'],
['International Business Machines',81.41,0.44,0.54,'9/1 12:00am'],
['Johnson & Johnson',64.72,0.06,0.09,'9/1 12:00am'],
['JP Morgan & Chase & Co',45.73,0.07,0.15,'9/1 12:00am'],
['McDonald\'s Corporation',36.76,0.86,2.40,'9/1 12:00am'],
['Merck & Co., Inc.',40.96,0.41,1.01,'9/1 12:00am'],
['Microsoft Corporation',25.84,0.14,0.54,'9/1 12:00am'],
['Pfizer Inc',27.96,0.4,1.45,'9/1 12:00am'],
['The Coca-Cola Company',45.07,0.26,0.58,'9/1 12:00am'],
['The Home Depot, Inc.',34.64,0.35,1.02,'9/1 12:00am'],
['The Procter & Gamble Company',61.91,0.01,0.02,'9/1 12:00am'],
['United Technologies Corporation',63.26,0.55,0.88,'9/1 12:00am'],
['Verizon Communications',35.57,0.39,1.11,'9/1 12:00am'],
['Wal-Mart Stores, Inc.',45.45,0.73,1.63,'9/1 12:00am']
];
/**
* Custom function used for column renderer
* @param {Object} val
*/
function change(val){
if(val > 0){
return '<span style="color:green;">' + val + '</span>';
}else if(val < 0){
return '<span style="color:red;">' + val + '</span>';
}
return val;
}
/**
* Custom function used for column renderer
* @param {Object} val
*/
function pctChange(val){
if(val > 0){
return '<span style="color:green;">' + val + '%</span>';
}else if(val < 0){
return '<span style="color:red;">' + val + '%</span>';
}
return val;
}
// create the data store
var store = new Ext.data.ArrayStore({
fields: [
{name: 'company'},
{name: 'price', type: 'float'},
{name: 'change', type: 'float'},
{name: 'pctChange', type: 'float'},
{name: 'lastChange', type: 'date', dateFormat: 'n/j h:ia'}
]
});
// manually load local data
store.loadData(myData);
// create the Grid
var grid = new Ext.grid.GridPanel({
store: store,
columns: [
{id:'company',header: 'Company', width: 160, sortable: true, dataIndex: 'company'},
{header: 'Price', width: 75, sortable: true, renderer: 'usMoney', dataIndex: 'price'},
{header: 'Change', width: 75, sortable: true, renderer: change, dataIndex: 'change'},
{header: '% Change', width: 75, sortable: true, renderer: pctChange, dataIndex: 'pctChange'},
{header: 'Last Updated', width: 85, sortable: true, renderer: Ext.util.Format.dateRenderer('m/d/Y'), dataIndex: 'lastChange'}
],
stripeRows: true,
autoExpandColumn: 'company',
height: 350,
width: 600,
title: 'Array Grid',
// config options for stateful behavior
stateful: true,
stateId: 'grid'
});
// render the grid to the specified div in the page
grid.render('grid-example');
});
Grid中有两个非常重要的属性，store和columns。store定义Grid需要展示的数据，columns定义Grid如何展示数据。在这个例子中主要也就是说说这两个属性如何设置。
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store（仓库），没错它就是数据仓库（不是那个数据仓库@o@）。在这个例子中给store属性赋的是Ext.data.ArrayStore的实例，实际上看看Ext的API就会知道有很多种store（ArrayStore, DirectStore, GroupingStore, JsonStore, XmlStore），其实在我开发的过程中最常用的是JsonStore，也就是根据后台回传的Json来组织数据仓库，后面应该还会说到。在本例中就直说ArrayStore的事，ArrayStore看名字得知这个根据数组组织store的。
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例子中给了数组的定义，如下：
// sample static data for the store
var myData = [
['3m Co',71.72,0.02,0.03,'9/1 12:00am'],
['Alcoa Inc',29.01,0.42,1.47,'9/1 12:00am'],
['Altria Group Inc',83.81,0.28,0.34,'9/1 12:00am'],
['American Express Company',52.55,0.01,0.02,'9/1 12:00am'],
['American International Group, Inc.',64.13,0.31,0.49,'9/1 12:00am'],
['AT&T Inc.',31.61,-0.48,-1.54,'9/1 12:00am'],
['Boeing Co.',75.43,0.53,0.71,'9/1 12:00am'],
['Caterpillar Inc.',67.27,0.92,1.39,'9/1 12:00am'],
['Citigroup, Inc.',49.37,0.02,0.04,'9/1 12:00am'],
['E.I. du Pont de Nemours and Company',40.48,0.51,1.28,'9/1 12:00am'],
['Exxon Mobil Corp',68.1,-0.43,-0.64,'9/1 12:00am'],
['General Electric Company',34.14,-0.08,-0.23,'9/1 12:00am'],
['General Motors Corporation',30.27,1.09,3.74,'9/1 12:00am'],
['Hewlett-Packard Co.',36.53,-0.03,-0.08,'9/1 12:00am'],
['Honeywell Intl Inc',38.77,0.05,0.13,'9/1 12:00am'],
['Intel Corporation',19.88,0.31,1.58,'9/1 12:00am'],
['International Business Machines',81.41,0.44,0.54,'9/1 12:00am'],
['Johnson & Johnson',64.72,0.06,0.09,'9/1 12:00am'],
['JP Morgan & Chase & Co',45.73,0.07,0.15,'9/1 12:00am'],
['McDonald\'s Corporation',36.76,0.86,2.40,'9/1 12:00am'],
['Merck & Co., Inc.',40.96,0.41,1.01,'9/1 12:00am'],
['Microsoft Corporation',25.84,0.14,0.54,'9/1 12:00am'],
['Pfizer Inc',27.96,0.4,1.45,'9/1 12:00am'],
['The Coca-Cola Company',45.07,0.26,0.58,'9/1 12:00am'],
['The Home Depot, Inc.',34.64,0.35,1.02,'9/1 12:00am'],
['The Procter & Gamble Company',61.91,0.01,0.02,'9/1 12:00am'],
['United Technologies Corporation',63.26,0.55,0.88,'9/1 12:00am'],
['Verizon Communications',35.57,0.39,1.11,'9/1 12:00am'],
['Wal-Mart Stores, Inc.',45.45,0.73,1.63,'9/1 12:00am']
];
实际上这是一个二维数组，每一个第二维的子数组都是一条记录的定义，每条记录中有5个字段，整个数组是由这样的多个子数组组成。在定义ArrayStore实例时还给出了fields的定义。
// create the data store
var store = new Ext.data.ArrayStore({
fields: [
{name: 'company'},
{name: 'price', type: 'float'},
{name: 'change', type: 'float'},
{name: 'pctChange', type: 'float'},
{name: 'lastChange', type: 'date', dateFormat: 'n/j h:ia'}
]
});
// manually load local data
store.loadData(myData);
在fields中按照子数组的顺序定义了五个字段，并分别起好了名字，还定义了字段的数据类型，默认是字符串类型的，所以company没有单独声明数据类型。在store中还定义了许多属性和方法，会在后面的例子中慢慢说到。
在定义了store中，例子中还调用了loadData方法，将数据加载到仓库中。其实也可以在定义store时就将data定义好，后面就不用在写loadData了，如：
// create the data store
var store = new Ext.data.ArrayStore({
fields: [
{name: 'company'},
{name: 'price', type: 'float'},
{name: 'change', type: 'float'},
{name: 'pctChange', type: 'float'},
{name: 'lastChange', type: 'date', dateFormat: 'n/j h:ia'}
],
data: myData
});
columns（列），定义Grid显示的列。
columns: [
{id:'company',header: 'Company', width: 160, sortable: true, dataIndex: 'company'},
{header: 'Price', width: 75, sortable: true, renderer: 'usMoney', dataIndex: 'price'},
{header: 'Change', width: 75, sortable: true, renderer: change, dataIndex: 'change'},
{header: '% Change', width: 75, sortable: true, renderer: pctChange, dataIndex: 'pctChange'},
{header: 'Last Updated', width: 85, sortable: true, renderer: Ext.util.Format.dateRenderer('m/d/Y'), dataIndex: 'lastChange'}
],
在这个例子中是这样定义columns属性的，其实也可以像定义store一样来定义columns，先声明一个变量再赋值给columns，如：
var cols = [
{id:'company',header: 'Company', width: 160, sortable: true, dataIndex: 'company'},
{header: 'Price', width: 75, sortable: true, renderer: 'usMoney', dataIndex: 'price'},
{header: 'Change', width: 75, sortable: true, renderer: change, dataIndex: 'change'},
{header: '% Change', width: 75, sortable: true, renderer: pctChange, dataIndex: 'pctChange'},
{header: 'Last Updated', width: 85, sortable: true, renderer: Ext.util.Format.dateRenderer('m/d/Y'), dataIndex: 'lastChange'}
];
// create the Grid
var grid = new Ext.grid.GridPanel({
store: store,
columns: cols,
…………
});
这里cols对应该数组Ext实际将其解析为Ext.grid.Column的对象，id定义当前字段是记录的标识，header定义表头显示的名字，width定义列宽，sortable定义是否允许以给列排序，dataIndex定义该列显示store中哪个字段，renderer定义显示该列要添加的格式。
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renderer显示的格式，Ext在Ext.util.Format中已经定义不少格式化的方法，在本例中使用了usMoney（美元）和dateRenderer（日期），除了已经定义好的，开发人员也可以自定义格式，如change和pctChange。
/**
* Custom function used for column renderer
* @param {Object} val
*/
function change(val){
if(val > 0){
return '<span style="color:green;">' + val + '</span>';
}else if(val < 0){
return '<span style="color:red;">' + val + '</span>';
}
return val;
}
/**
* Custom function used for column renderer
* @param {Object} val
*/
function pctChange(val){
if(val > 0){
return '<span style="color:green;">' + val + '%</span>';
}else if(val < 0){
return '<span style="color:red;">' + val + '%</span>';
}
return val;
}
格式化方法接收一个参数，那就是要格式化的值，返回一个结果是格式化后的值。
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在Grid的定义中还有：
autoExpandColumn: 'company',
这句话定义了列'company'是自动扩展列，会根据内容自动扩展给列的宽度
title: 'Array Grid',
定义整个列表的标题，如果不写该行，则列表（Grid）不显示标题。
height: 350, width: 600,
定义Grid的高度和宽度
stateful: true, stateId: 'grid'
当stateful为真时，保存当前列表的状态，如按照哪列排序、列宽、列的先后位置；stateId指明了保存状态的ID，若不指定该属性则无法保存列表状态。
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例子的最后一行
grid.render('grid-example');
让表格显示在id为“grid-example”的div中。
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本例打完收工。