Access SQL database from an iPhone app Via RESTful WCF service - ios

Question

I have created a small project that can read and insert data from iPhone to sql server via RESTful WCF service.
I have read the data successfully with the following approach:
1- I have created a wcf web service that read data from Sql serverwith table Employees(firstname,lastname,salary):
"41.142.251.142/JsonWcfService/GetEmployees.svc/json/employees"
2- I have created a new project in xcode 5.0.2, and I added a textfield (viewData.text) to display data retrieved by the web service.
3- I added the following instruction in my viewController.m :
"#define WcfSeviceURL [NSURL URLWithString: #"41.142.251.142/JsonWcfService/GetEmployees.svc/json/employees"]"
3- In (void)viewDidLoad method, I implemented the below code:
- (void)viewDidLoad
{
[super viewDidLoad];
NSError *error = nil;
NSData *data = [NSData dataWithContentsOfURL:WcfSeviceURL options:NSDataReadingUncached error:&error];
if(!error)
{
NSDictionary* json = [NSJSONSerialization
JSONObjectWithData:data
options:NSJSONReadingMutableContainers
error:&error];
NSMutableArray *array= [json objectForKey:#"GetAllEmployeesMethodResult"];
for(int i=0; i< array.count; i++)
{
NSDictionary *empInfo= [array objectAtIndex:i];
NSString *first = [empInfo objectForKey:#"firstname"];
NSString *last = [empInfo objectForKey:#"lastname"];
NSString *salary = [empInfo objectForKey:#"salary"];
//Take out whitespaces from String
NSString *firstname = [first
stringByReplacingOccurrencesOfString:#" " withString:#""];
NSString *lastname = [last
stringByReplacingOccurrencesOfString:#" " withString:#""];
viewData.text= [viewData.text stringByAppendingString:[NSString stringWithFormat:#"%# %# makes $%#.00 per year.\n",firstname,lastname,salary]];
}
}
}
Check the following link : http://www.codeproject.com/Articles/405189/How-to-access-SQL-database-from-an-iPhone-app-Via.
As I mentioned, I can read the data from my iPhone without any problem.
So the second step is how to write and insert data from the iPhone to sql server.
for this, I created first the method that insert data in my webservice:
In WCF interface:
[OperationContract]
[WebInvoke(Method = "POST",
ResponseFormat = WebMessageFormat.Json,
RequestFormat = WebMessageFormat.Json,
BodyStyle = WebMessageBodyStyle.Wrapped,
UriTemplate = "json/InsertEmployee/{id1}/{id2}/{id3}")]
bool InsertEmployeeMethod(string id1,string id2, string id3);
In Implementation:
public bool InsertEmployeeMethod(string id1,string id2, string id3)
{
int success = 0;
using (SqlConnection conn = new SqlConnection("server=(local);database=EmpDB;Integrated Security=SSPI;"))
{
conn.Open();
decimal value= Decimal.Parse(id3);
string cmdStr = string.Format("INSERT INTO EmpInfo VALUES('{0}','{1}',{2})",id1,id2,value);
SqlCommand cmd = new SqlCommand(cmdStr, conn);
success = cmd.ExecuteNonQuery();
conn.Close();
}
return (success != 0 ? true : false);
}
So to test this web servcie method use:
"41.142.251.142/JsonWcfService/GetEmployees.svc/json/InsertEmployee/myName/MylastName/6565"
Then to consume this method from iPhone I used the following approach:
I decalared the Define Instruction:
"#define BaseWcfUrl [NSURL URLWithString:
#"41.142.251.142/JsonWcfService/GetEmployees.svc/json/InsertEmployee/{id1}/{id2}/{id3}"]"
Then I implemented the Insert Employee Method related to click button.
-(void) insertEmployeeMethod
{
if(firstname.text.length && lastname.text.length && salary.text.length)
{
NSString *str = [BaseWcfUrl stringByAppendingFormat:#"InsertEmployee/%#/%#/%#",firstname.text,lastname.text,salary.text];
NSURL *WcfServiceURL = [NSURL URLWithString:str];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:WcfServiceURL];
[request setHTTPMethod:#"POST"];
// connect to the web
NSData *respData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
// NSString *respStr = [[NSString alloc] initWithData:respData encoding:NSUTF8StringEncoding];
NSError *error;
NSDictionary* json = [NSJSONSerialization
JSONObjectWithData:respData
options:NSJSONReadingMutableContainers
error:&error];
NSNumber *isSuccessNumber = (NSNumber*)[json objectForKey:#"InsertEmployeeMethodResult"];
//create some label field to display status
status.text = (isSuccessNumber && [isSuccessNumber boolValue] == YES) ? [NSString stringWithFormat:#"Inserted %#, %#",firstname.text,lastname.text]:[NSString stringWithFormat:#"Failed to insert %#, %#",firstname.text,lastname.text];
}
}
But the issue here, is in the following instruction:
NSString *str = [BaseWcfUrl stringByAppendingFormat:#"InsertEmployee/%#/%#/%#",firstname.text,lastname.text,salary.text];
Always the system returns a message 'Data parameter nil' with this line, knowing that the firstname.text, and lastname.text, salary are all filled and I can see their values with NSLog(#"First Name :%#",firstname.text)...
Can you please help on this?
Thanks in advance.

Answer 1

I don't think NSURLs stringByAppendingFormat will do what you want.
Try something like this:
#define kBase_URL #"41.142.251.142/JsonWcfService/GetEmployees.svc/json/%#"
#define kAuthAPI_InsertEmployee_URL [NSString stringWithFormat:kBase_URL, #"InsertEmployee/%#/%#/%#"]
//Setup session
NSError *error;
NSURL *requestURL = [NSURL URLWithString:[NSString stringWithFormat:kAuthAPI_InsertEmployee_URL,firstname.text,lastname.text,salary.text]];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:requestURL cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:60.0];
[request addValue:#"application/json" forHTTPHeaderField:#"Content-Type"];
[request addValue:#"application/json" forHTTPHeaderField:#"Accept"];
[request setHTTPMethod:#"POST"];
NSData *postData = [NSJSONSerialization dataWithJSONObject:profileData options:0 error:&error];
[request setHTTPBody:postData];
etc. etc.