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

			}catch(execError){
				error = true;
				exp = execError.message||execError;
			}
		
			// was there an error during SQL execution?
			if(exp != null){
				if(dojox.sql._autoClose){
					try{ dojox.sql.close(); }catch(e){}
				}
			
				callback(null, true, exp.toString());
				return;
			}
		
			// normalize SQL results into a JavaScript object 
			// we can work with
			resultSet = dojox.sql._normalizeResults(resultSet);
		
			if(dojox.sql._autoClose){
				dojox.sql.close();
			}
				
			// are any decryptions necessary on the result set?
			if(dojox.sql._needsDecrypt(sql)){
				// determine which of the result set columns needs decryption
	 			var needsDecrypt = self._determineDecryptedColumns(sql);

				// now decrypt columns asynchronously
				// decrypt columns that need it
				self._decrypt(resultSet, needsDecrypt, password, function(finalResultSet){
					callback(finalResultSet, false, null);
				});
			}else{
				callback(resultSet, false, null);
			}
		});
	},

	_execDecryptSQL: function(sql, password, args, callback){
		// strip the ENCRYPT/DECRYPT keywords from the SQL
		var strippedSQL = this._stripCryptoSQL(sql);
	
		// determine which columns needs decryption; this either
		// returns the value *, which means all result set columns will
		// be decrypted, or it will return the column names that need
		// decryption set on a hashtable so we can quickly test a given
		// column name; the key is the column name that needs
		// decryption and the value is 'true' (i.e. needsDecrypt["someColumn"] 
		// would return 'true' if it needs decryption, and would be 'undefined'
		// or false otherwise)
		var needsDecrypt = this._determineDecryptedColumns(sql);
	
		// execute the SQL
		var error = false;
		var resultSet = [];
		var exp = null;
		try{
			resultSet = dojox.sql.db.execute(strippedSQL, args);
		}catch(execError){
			error = true;
			exp = execError.message||execError;
		}
	
		// was there an error during SQL execution?
		if(exp != null){
			if(dojox.sql._autoClose){
				try{ dojox.sql.close(); }catch(e){}
			}
		
			callback(resultSet, true, exp.toString());
			return;
		}
	
		// normalize SQL results into a JavaScript object 
		// we can work with
		resultSet = dojox.sql._normalizeResults(resultSet);
	
		if(dojox.sql._autoClose){
			dojox.sql.close();
		}
	
		// decrypt columns that need it
		this._decrypt(resultSet, needsDecrypt, password, function(finalResultSet){
			callback(finalResultSet, false, null);
		});
	},

	_encrypt: function(sql, password, args, encryptColumns, callback){
		//console.debug("_encrypt, sql="+sql+", password="+password+", encryptColumns="+encryptColumns+", args="+args);
	
		this._totalCrypto = 0;
		this._finishedCrypto = 0;
		this._finishedSpawningCrypto = false;
		this._finalArgs = args;
	
		for(var i = 0; i < args.length; i++){
			if(encryptColumns[i]){
				// we have an encrypt() keyword -- get just the value inside
				// the encrypt() parantheses -- for now this must be a ?
				var sqlParam = args[i];
				var paramIndex = i;
			
				// update the total number of encryptions we know must be done asynchronously
				this._totalCrypto++;
			
				// FIXME: This currently uses DES as a proof-of-concept since the
				// DES code used is quite fast and was easy to work with. Modify dojox.sql
				// to be able to specify a different encryption provider through a 
				// a SQL-like syntax, such as dojox.sql("SET ENCRYPTION BLOWFISH"),
				// and modify the dojox.crypto.Blowfish code to be able to work using
				// a Google Gears Worker Pool
			
				// do the actual encryption now, asychronously on a Gears worker thread
				dojox._sql._crypto.encrypt(sqlParam, password, dojo.hitch(this, function(results){
					// set the new encrypted value
					this._finalArgs[paramIndex] = results;
					this._finishedCrypto++;
					// are we done with all encryption?
					if(this._finishedCrypto >= this._totalCrypto
						&& this._finishedSpawningCrypto){
						callback(this._finalArgs);
					}
				}));
			}
		}
	
		this._finishedSpawningCrypto = true;
	},

	_decrypt: function(resultSet, needsDecrypt, password, callback){
		//console.debug("decrypt, resultSet="+resultSet+", needsDecrypt="+needsDecrypt+", password="+password);
		
		this._totalCrypto = 0;
		this._finishedCrypto = 0;
		this._finishedSpawningCrypto = false;
		this._finalResultSet = resultSet;
	
		for(var i = 0; i < resultSet.length; i++){
			var row = resultSet[i];
		
			// go through each of the column names in row,
			// seeing if they need decryption
			for(var columnName in row){
				if(needsDecrypt == "*" || needsDecrypt[columnName]){
					this._totalCrypto++;
					var columnValue = row[columnName];
				
					// forming a closure here can cause issues, with values not cleanly
					// saved on Firefox/Mac OS X for some of the values above that
					// are needed in the callback below; call a subroutine that will form 
					// a closure inside of itself instead
					this._decryptSingleColumn(columnName, columnValue, password, i,
												function(finalResultSet){
						callback(finalResultSet);
					});
				}
			}
		}
	
		this._finishedSpawningCrypto = true;
	},

	_stripCryptoSQL: function(sql){
		// replace all DECRYPT(*) occurrences with a *
		sql = sql.replace(/DECRYPT\(\*\)/ig, "*");
	
		// match any ENCRYPT(?, ?, ?, etc) occurrences,
		// then replace with just the question marks in the
		// middle
		var matches = sql.match(/ENCRYPT\([^\)]*\)/ig);
		if(matches != null){
			for(var i = 0; i < matches.length; i++){
				var encryptStatement = matches[i];
				var encryptValue = encryptStatement.match(/ENCRYPT\(([^\)]*)\)/i)[1];
				sql = sql.replace(encryptStatement, encryptValue);
			}
		}
	
		// match any DECRYPT(COL1, COL2, etc) occurrences,
		// then replace with just the column names
		// in the middle
		matches = sql.match(/DECRYPT\([^\)]*\)/ig);
		if(matches != null){
			for(var i = 0; i < matches.length; i++){
				var decryptStatement = matches[i];
				var decryptValue = decryptStatement.match(/DECRYPT\(([^\)]*)\)/i)[1];
				sql = sql.replace(decryptStatement, decryptValue);
			}
		}
	
		return sql;
	},

	_flagEncryptedArgs: function(sql, args){
		// capture literal strings that have question marks in them,
		// and also capture question marks that stand alone
		var tester = new RegExp(/([\"][^\"]*\?[^\"]*[\"])|([\'][^\']*\?[^\']*[\'])|(\?)/ig);
		var matches;
		var currentParam = 0;
		var results = [];
		while((matches = tester.exec(sql)) != null){
			var currentMatch = RegExp.lastMatch+"";

			// are we a literal string? then ignore it
			if(/^[\"\']/.test(currentMatch)){
				continue;
			}

			// do we have an encrypt keyword to our left?
			var needsEncrypt = false;
			if(/ENCRYPT\([^\)]*$/i.test(RegExp.leftContext)){
				needsEncrypt = true;
			}

			// set the encrypted flag
			results[currentParam] = needsEncrypt;

			currentParam++;
		}
	
		return results;
	},

	_determineDecryptedColumns: function(sql){
		var results = {};

		if(/DECRYPT\(\*\)/i.test(sql)){
			results = "*";
		}else{
			var tester = /DECRYPT\((?:\s*\w*\s*\,?)*\)/ig;
			var matches;
			while(matches = tester.exec(sql)){
				var lastMatch = new String(RegExp.lastMatch);
				var columnNames = lastMatch.replace(/DECRYPT\(/i, "");
				columnNames = columnNames.replace(/\)/, "");
				columnNames = columnNames.split(/\s*,\s*/);
				dojo.forEach(columnNames, function(column){
					if(/\s*\w* AS (\w*)/i.test(column)){
						column = column.match(/\s*\w* AS (\w*)/i)[1];
					}
					results[column] = true;
				});
			}
		}

		return results;
	},

	_decryptSingleColumn: function(columnName, columnValue, password, currentRowIndex,
											callback){
		//console.debug("decryptSingleColumn, columnName="+columnName+", columnValue="+columnValue+", currentRowIndex="+currentRowIndex)
		dojox._sql._crypto.decrypt(columnValue, password, dojo.hitch(this, function(results){
			// set the new decrypted value
			this._finalResultSet[currentRowIndex][columnName] = results;
			this._finishedCrypto++;
			
			// are we done with all encryption?
			if(this._finishedCrypto >= this._totalCrypto
				&& this._finishedSpawningCrypto){
				//console.debug("done with all decrypts");
				callback(this._finalResultSet);
			}
		}));
	}
});

}