download.permsoft.com | ||
.NET/ASP.NET/C#/VB.NET PDF Document SDKAs you ve already seen, the opening tag of the <authentication> element supports a mode attribute that is used to establish the level of authentication for your web application. This element may include an optional <forms> or <passport> subelement based on your authentication choice. Given this, the basic skeleton of the <authentication> section of a web.config file is as so (where the pipe notation (|) represents selecting a single member of the set): <authentication mode="Windows | Forms | Passport | None"> <forms/> <passport/> </authentication> barcode in excel 2010, download barcode for excel 2010, create barcode in excel vba, activebarcode excel 2010, microsoft excel barcode generator, barcode inventory excel program, free 2d barcode font excel, excel barcode inventory template, free barcode fonts for microsoft office, how to make barcodes in excel 2011,When this code is executed, we get the correct answer. This is because, during execution, the roles were enabled, as we had created the procedure with invoker rights. Hence, the procedure runs successfully: invoker@ORA10G> exec invoker_mode_proc Count is : 5 Note that if you use dynamic SQL with the definer rights procedure, you ll be able to compile the code, but you ll get a runtime error if you don t have direct privileges on the accessed object. To demonstrate this, let s connect as sys and revoke the direct select privilege on t1 from the user definer: sys@ORA10G> revoke select on t1 from definer; Revoke succeeded. If we now connect back as the user definer and try to compile the procedure definer_mode_proc, which now uses dynamic SQL, the compilation will work: sys@ORA10G> conn definer/definer Connected. definer@ORA10G definer@ORA10G> create or replace procedure definer_mode_proc 2 is 3 l_count number; 4 begin 5 execute immediate 'select count(*) from t1' into l_count; 6 dbms_output.put_line( 'Count is : ' || l_count ); 7 end; 8 / Procedure created. However, when we execute the procedure, since roles are disabled, we will get an error: definer@ORA10G> execute definer_mode_proc BEGIN definer_mode_proc; END; * ERROR at line 1: ORA-00942: table or view does not exist ORA-06512: at "DEFINER.DEFINER_MODE_PROC", line 5 ORA-06512: at line 1 Exceptions may also be processed using the try ... finally ... construct. This guarantees to run the finally clause both when an exception is thrown and when the expression evaluates normally. This allows the programmer to ensure that resources are disposed after the completion This example demonstrates how invoker rights procedures differ from definer rights procedures in terms of roles being enabled or disabled during program execution. Let s look at another example to see how these two modes differ in terms of object resolution. Say we want to write a generic routine that will return the number of rows of a given table or view. We do not want to create this procedure in multiple schemas we want to create it once and let others share the same code. For such generic code, it is a good idea to create a separate schema. We create one called utils as follows: sys@ORA10G> create user utils identified by utils; User created. sys@ORA10G> grant create session, 2 create procedure, 3 create public synonym, 4 drop public synonym 5 to utils; Grant succeeded. We now connect as utils and create a function, count_rows(), that takes a table name as a parameter and uses dynamic SQL to return the number of rows: utils@ORA10G> create or replace function count_rows( p_table_name in varchar2 ) 2 return number 3 is 4 l_count number; 5 begin 6 execute immediate 'select count(*) from ' || p_table_name into l_count; 7 return l_count; 8 end; 9 / Function created. Since we want this function to be used by other schemas, we create a public synonym and also grant the execute privilege on this function to public: utils@ORA10G> grant execute on count_rows to public; Grant succeeded. utils@ORA10G> create public synonym count_rows for count_rows; Synonym created. of an operation. For example, we can ensure that the web response from the previous example is closed as follows: let httpViaTryFinally(url: string) = let req = System.Net.WebRequest.Create(url) let resp = req.GetResponse() try let stream = resp.GetResponseStream() let reader = new StreamReader(stream) let html = reader.ReadToEnd() html finally resp.Close() In practice, you can use a shorter form to close and dispose of resources, simply by using a use binding instead of a let binding. This closes the response at the end of the scope of the resp variable, a technique is discussed in full in 8. Here is how the previous function looks using this form: let httpViaUseBinding(url: string) = let req = System.Net.WebRequest.Create(url) use resp = req.GetResponse() let stream = resp.GetResponseStream() let reader = new StreamReader(stream) let html = reader.ReadToEnd() html
|