sqlite操作类（html5 js）

[javascript]代码库

var lanxDB=function ( dbname )
{
	var db=openDatabase ( dbname,'1.0.0','',65536 );
	return
	{
		// 返回数据库名
getDBName:
		function()
		{
			return dbname;
		},
		// 初始化数据库，如果需要则创建表
init:
		function ( tableName,colums )
		{
			this.switchTable ( tableName );
			colums.length>0?this.createTable ( colums ) :'';
			return this;
		},
		// 创建表，colums:[name:字段名,type:字段类型]
createTable:
		function ( colums )
		{
			var sql="CREATE TABLE IF NOT EXISTS " + this._table ;
			var t;
			if ( colums instanceof Array && colums.length>0 )
			{
				t=[];
				for ( var i in colums )
				{
					t.push ( colums[i].name+' '+colums[i].type );
				}
				t=t.join ( ', ' );
			}
			else if ( typeof colums=="object" )
			{
				t+=colums.name+' '+colums.type;
			}
			sql=sql+" ("+t+")";
			var that=this;
			db.transaction ( function ( t )
			{
				t.executeSql ( sql ) ;
			} )
		},
		// 切换表
switchTable:
		function ( tableName )
		{
			this._table=tableName;
			return this;
		},
		// 插入数据并执行回调函数，支持批量插入
		// data为Array类型，每一组值均为Object类型，每一个Obejct的属性应为表的字段名，

		对应要保存的值
insertData:
		function ( data,callback )
		{
			var that=this;
			var sql="INSERT INTO "+this._table;
			if ( data instanceof Array && data.length>0 )
			{
				var cols=[],qs=[];
				for ( var i in data[0] )
				{
					cols.push ( i );
					qs.push ( '?' );
				}
				sql+=" ("+cols.join ( ',' ) +") Values ("+qs.join ( ',' ) +")";
			}
			else
			{
				return false;
			}
			var p=[],
			      d=data,
			        pLenth=0,
			               r=[];
			for ( var i=0,dLength=d.length; i     var k=[];
			        for ( var j in d[i] )
			{
				k.push ( d[i][j] );
				}
			p.push ( k );
		}
		var queue=function ( b,result )
		{
			if ( result )
			{
				r.push ( result.insertId ||result.rowsAffected );
			}
			if ( p.length>0 )
			{
				db.transaction ( function ( t )
				{
					t.executeSql ( sql,p.shift(),queue,that.onfail );
				} )
			}
			else
			{
				if ( callback )
				{
					callback.call ( this,r );
				}
			}
		}
		queue();
	},
_where:''
	,
	// where语句，支持自写和以对象属性值对的形式
where:
	function ( where )
	{
		if ( typeof where==='object' )
		{
			var j=this.toArray ( where );
			this._where=j.join ( ' and ' );
		}
		else if ( typeof where==='string' )
		{
			this._where=where;
		}
		return this;
	},
	// 更新数据，data为属性值对形式
updateData:
	function ( data,callback )
	{
		var that=this;
		var sql="Update "+this._table;
		data=this.toArray ( data ).join ( ',' );
		sql+=" Set "+data+" where "+this._where;
		this.doQuery ( sql,callback );
	},
	// 根据条件保存数据，如果存在则更新，不存在则插入数据
saveData:
	function ( data,callback )
	{
		var sql="Select * from "+this._table+" where "+this._where;
		var that=this;
		this.doQuery ( sql,function ( r )
		{
			if ( r.length>0 )
			{
				that.updateData ( data,callback );
			}
			else
			{
				that.insertData ( [data],callback );
			}
		} );
	},
	// 获取数据
getData:
	function ( callback )
	{
		var that=this;
		var sql="Select * from "+that._table;
		that._where.length>0?sql+=" where "+that._where:"";
		that.doQuery ( sql,callback );
	},
	// 查询，内部方法
doQuery:
	function ( sql,callback )
	{
		var that=this;
		var a=[];
		var bb=function ( b,result )
		{
			if ( result.rows.length )
			{
				for ( var i=0; i       a.push ( result.rows.item ( i ) );
			        }
	        }
	        else
	{
		a.push ( result.rowsAffected );
		}
		if ( callback )
		{
			callback.call ( that,a );
		}
	}
	db.transaction ( function ( t )
	{
		t.executeSql ( sql,[],bb,that.onfail ) ;
	} )
},
// 根据条件删除数据
deleteData:
function ( callback )
{
	var that=this;
	var sql="delete from "+that._table;
	that._where.length>0?sql+=" where "+that._where:'';
	that.doQuery ( sql,callback );
},
// 删除表
dropTable:
function()
{
	var sql="DROP TABLE IF EXISTS "+this._table;
	this.doQuery ( sql );
},
_error:''
,
onfail:
function ( t,e )
{
	this._error=e.message;
	console.log ( '----sqlite:'+e.message );
},
toArray:
function ( obj )
{
	var t=[];
	obj=obj || {};
	if ( obj )
	{
		for ( var i in obj )
		{
			t.push ( i+"='"+obj[i]+"'" );
		}
	}
	return t;
}
}
}

/*
 examples:
var db = new lanxDB('testDB');
db.init('channel_list', [ {
	name : 'id',
	type : 'integer primary key autoincrement'
},

{
	name : 'name',
	type : 'text'
}, {
	name : 'link',
	type : 'text'
}, {
	name : 'cover',
	type : 'text'
},

{
	name : 'updatetime',
	type : 'integer'
}, {
	name : 'orders',
	type : 'integer'
} ]);
db.init('feed_list', [ {
	name : 'parentid',
	type : 'integer'
},

{
	name : 'feed',
	type : 'text'
} ]);
db.switchTable('channel_list').insertData([ {
	name : 'aa',
	link : 'ss',
	updatetime : new

	Date().getTime()
}, {
	name : 'bb',
	link : 'kk',
	updatetime : new Date().getTime()
} ]);
db.where({
	name : 'aa'
}).getData(function(result) {
	console.log(result);// result为Array
});
db.where({
	name : 'aa'
}).deleteData(function(result) {
	console.log(result[0]);// 删除条数
});
db.where({
	name : 'bb'
}).saveData({
	link : 'jj'
}, function(result) {
	console.log(result);// 影响条数
})})
 */