common.js

这是一个ajax的例子大家好好的看看就是一个鱼眼的效果

if(!dojo._hasResource["dojox._sql.common"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
dojo._hasResource["dojox._sql.common"] = true;
dojo.provide("dojox._sql.common");

dojo.require("dojox._sql._crypto");

// summary:
//	Executes a SQL expression.
// description:
// 	There are four ways to call this:
// 	1) Straight SQL: dojox.sql("SELECT * FROM FOOBAR");
// 	2) SQL with parameters: dojox.sql("INSERT INTO FOOBAR VALUES (?)", someParam)
// 	3) Encrypting particular values: 
//			dojox.sql("INSERT INTO FOOBAR VALUES (ENCRYPT(?))", someParam, "somePassword", callback)
// 	4) Decrypting particular values:
//			dojox.sql("SELECT DECRYPT(SOMECOL1), DECRYPT(SOMECOL2) FROM
//					FOOBAR WHERE SOMECOL3 = ?", someParam,
//					"somePassword", callback)
//
// 	For encryption and decryption the last two values should be the the password for
// 	encryption/decryption, and the callback function that gets the result set.
//
// 	Note: We only support ENCRYPT(?) statements, and
// 	and DECRYPT(*) statements for now -- you can not have a literal string
// 	inside of these, such as ENCRYPT('foobar')
//
// 	Note: If you have multiple columns to encrypt and decrypt, you can use the following
// 	convenience form to not have to type ENCRYPT(?)/DECRYPT(*) many times:
//
// 	dojox.sql("INSERT INTO FOOBAR VALUES (ENCRYPT(?, ?, ?))", 
//					someParam1, someParam2, someParam3, 
//					"somePassword", callback)
//
// 	dojox.sql("SELECT DECRYPT(SOMECOL1, SOMECOL2) FROM
//					FOOBAR WHERE SOMECOL3 = ?", someParam,
//					"somePassword", callback)
dojox.sql = new Function("return dojox.sql._exec(arguments);");

dojo.mixin(dojox.sql, {
	dbName: null,
	
	// summary:
	//	If true, then we print out any SQL that is executed
	//	to the debug window
	debug: (dojo.exists("dojox.sql.debug")?dojox.sql.debug:false),

	open: function(dbName){
		if(this._dbOpen && (!dbName || dbName == this.dbName)){
			return;
		}
		
		if(!this.dbName){
			this.dbName = "dot_store_" 
				+ window.location.href.replace(/[^0-9A-Za-z_]/g, "_");
			// database names in Gears are limited to 64 characters long
			if(this.dbName.length > 63){
			  this.dbName = this.dbName.substring(0, 63);
			}
		}
		
		if(!dbName){
			dbName = this.dbName;
		}
		
		try{
			this._initDb();
			this.db.open(dbName);
			this._dbOpen = true;
		}catch(exp){
			throw exp.message||exp;
		}
	},

	close: function(dbName){
		// on Internet Explorer, Google Gears throws an exception
		// "Object not a collection", when we try to close the
		// database -- just don't close it on this platform
		// since we are running into a Gears bug; the Gears team
		// said it's ok to not close a database connection
		if(dojo.isIE){ return; }
		
		if(!this._dbOpen && (!dbName || dbName == this.dbName)){
			return;
		}
		
		if(!dbName){
			dbName = this.dbName;
		}
		
		try{
			this.db.close(dbName);
			this._dbOpen = false;
		}catch(exp){
			throw exp.message||exp;
		}
	},
	
	_exec: function(params){
		try{	
			// get the Gears Database object
			this._initDb();
		
			// see if we need to open the db; if programmer
			// manually called dojox.sql.open() let them handle
			// it; otherwise we open and close automatically on
			// each SQL execution
			if(!this._dbOpen){
				this.open();
				this._autoClose = true;
			}
		
			// determine our parameters
			var sql = null;
			var callback = null;
			var password = null;

			var args = dojo._toArray(params);

			sql = args.splice(0, 1)[0];

			// does this SQL statement use the ENCRYPT or DECRYPT
			// keywords? if so, extract our callback and crypto
			// password
			if(this._needsEncrypt(sql) || this._needsDecrypt(sql)){
				callback = args.splice(args.length - 1, 1)[0];
				password = args.splice(args.length - 1, 1)[0];
			}

			// 'args' now just has the SQL parameters

			// print out debug SQL output if the developer wants that
			if(this.debug){
				this._printDebugSQL(sql, args);
			}

			// handle SQL that needs encryption/decryption differently
			// do we have an ENCRYPT SQL statement? if so, handle that first
			if(this._needsEncrypt(sql)){
				var crypto = new dojox.sql._SQLCrypto("encrypt", sql, 
													password, args, 
													callback);
				return; // encrypted results will arrive asynchronously
			}else if(this._needsDecrypt(sql)){ // otherwise we have a DECRYPT statement
				var crypto = new dojox.sql._SQLCrypto("decrypt", sql, 
													password, args, 
													callback);
				return; // decrypted results will arrive asynchronously
			}

			// execute the SQL and get the results
			var rs = this.db.execute(sql, args);
			
			// Gears ResultSet object's are ugly -- normalize
			// these into something JavaScript programmers know
			// how to work with, basically an array of 
			// JavaScript objects where each property name is
			// simply the field name for a column of data
			rs = this._normalizeResults(rs);
		
			if(this._autoClose){
				this.close();
			}
		
			return rs;
		}catch(exp){
			exp = exp.message||exp;
			
			console.debug("SQL Exception: " + exp);
			
			if(this._autoClose){
				try{ 
					this.close(); 
				}catch(e){
					console.debug("Error closing database: " 
									+ e.message||e);
				}
			}
		
			throw exp;
		}
	},

	_initDb: function(){
		if(!this.db){
			try{
				this.db = google.gears.factory.create('beta.database', '1.0');
			}catch(exp){
				dojo.setObject("google.gears.denied", true);
				dojox.off.onFrameworkEvent("coreOperationFailed");
				throw "Google Gears must be allowed to run";
			}
		}
	},

	_printDebugSQL: function(sql, args){
		var msg = "dojox.sql(\"" + sql + "\"";
		for(var i = 0; i < args.length; i++){
			if(typeof args[i] == "string"){
				msg += ", \"" + args[i] + "\"";
			}else{
				msg += ", " + args[i];
			}
		}
		msg += ")";
	
		console.debug(msg);
	},

	_normalizeResults: function(rs){
		var results = [];
		if(!rs){ return []; }
	
		while(rs.isValidRow()){
			var row = {};
		
			for(var i = 0; i < rs.fieldCount(); i++){
				var fieldName = rs.fieldName(i);
				var fieldValue = rs.field(i);
				row[fieldName] = fieldValue;
			}
		
			results.push(row);
		
			rs.next();
		}
	
		rs.close();
		
		return results;
	},

	_needsEncrypt: function(sql){
		return /encrypt\([^\)]*\)/i.test(sql);
	},

	_needsDecrypt: function(sql){
		return /decrypt\([^\)]*\)/i.test(sql);
	}
});

// summary:
//	A private class encapsulating any cryptography that must be done
// 	on a SQL statement. We instantiate this class and have it hold
//	it's state so that we can potentially have several encryption
//	operations happening at the same time by different SQL statements.
dojo.declare("dojox.sql._SQLCrypto", null, {
	constructor: function(action, sql, password, args, callback){
		if(action == "encrypt"){
			this._execEncryptSQL(sql, password, args, callback);
		}else{
			this._execDecryptSQL(sql, password, args, callback);
		}		
	}, 
	
	_execEncryptSQL: function(sql, password, args, callback){
		// strip the ENCRYPT/DECRYPT keywords from the SQL
		var strippedSQL = this._stripCryptoSQL(sql);
	
		// determine what arguments need encryption
		var encryptColumns = this._flagEncryptedArgs(sql, args);
	
		// asynchronously encrypt each argument that needs it
		var self = this;
		this._encrypt(strippedSQL, password, args, encryptColumns, function(finalArgs){
			// execute the SQL
			var error = false;
			var resultSet = [];
			var exp = null;
			try{
				resultSet = dojox.sql.db.execute(strippedSQL, finalArgs);