I am trying to insert data into a database that I have that has a table called EmployeeInfo
The user is prompted to enter a last name and select a department ID (displayed to the user as either marketing or development) The column ID automatically increments.
Here is my Code behind
protected void SubmitEmployee_Click(object sender, EventArgs e)
{
var submittedEmployeeName = TextBox1.Text;
var submittedDepartment = selectEmployeeDepartment.Text;
if (submittedEmployeeName == "")
{
nameError.Text = "*Last name cannot be blank";
}
else
{
System.Data.SqlClient.SqlConnection sqlConnection1 =
new System.Data.SqlClient.SqlConnection("ConnString");
System.Data.SqlClient.SqlCommand cmd = new System.Data.SqlClient.SqlCommand();
cmd.CommandType = System.Data.CommandType.Text;
cmd.CommandText = "INSERT INTO EmployeeInfo (LastName, DepartmentID ) VALUES ('" + submittedEmployeeName + "', " + submittedDepartment + ")";
cmd.Connection = sqlConnection1;
sqlConnection1.Open();
cmd.ExecuteNonQuery();
sqlConnection1.Close();
}
}
The error I'm recieving is 'Arguement exception was unhandled by user code'
Here is a picture of it.
As requested. More details
If I had enough reputation, I would rather post this as a reply, but it might actually be the solution.
The reason why it stops there is because you are not providing a legit SqlConnection, since your input is: "ConnString", which is just that text.
The connection string should look something like:
const string MyConnectionString = "SERVER=localhost;DATABASE=DbName;UID=userID;PWD=userPW;"
Which in your case should end up like:
System.Data.SqlClient.SqlConnection sqlConnection1 = new System.Data.SqlClient.SqlConnection(MyConnectionString);
Besides that, you should build your connections like following:
using (SqlConnection con = new SqlConnection(MyConnectionString)) {
using (SqlCommand cmd = new SqlCommand())
{
cmd.CommandText = xxxxxx; // Your query to the database
cmd.Connection = con;
cmd.Connection.Open();
cmd.ExecuteNonQuery();
}
}
This will do the closing for you and it also makes it easier for you to nestle connections. I did a project recently and did the connection your way, which ended up not working when I wanted to do more than one execute in one function. Just important to make a new command for each execute.
Related
I'm trying to delete record from data base MSSQL by entering the ID and hit delete btn. i didn't get any error and it give recorded deleted successful but once i check database i see the record doesn't deleted
protected void btnDelete_Click(object sender, EventArgs e)
{
try
{
if (txtImgID.Text == "")
{
Response.Write("Enter Image Id To Delete");
}
else
{
SqlCommand cmd = new SqlCommand();
SqlConnection con = new SqlConnection();
con = new SqlConnection(ConfigurationManager.ConnectionStrings["GMSConnectionString"].ConnectionString);
con.Open();
cmd = new SqlCommand("delete from certf where id=" + txtImgID.Text + "", con);
lblsubmitt.Text = "Data Deleted Sucessfully";
}
}
catch (Exception)
{
lblsubmitt.Text = "You haven't Submited any data";
}
}
var idToDelete = int.Parse(txtImgID.Text); // this is not necessary if the data type in the DB is actually a string
using (SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["GMSConnectionString"].ConnectionString))
using (SqlCommand cmd = new SqlCommand("DELETE FROM [certf] WHERE id = #id", con))
{
// I am assuming that id is an integer but if it is a varchar/string then use the line below this one
// cmd.Parameters.Add("#id", SqlDbType.VarChar, 100).Value = txtImgID.Text;
cmd.Parameters.Add("#id", SqlDbType.Int32).Value = idToDelete;
cmd.ExecuteNonQuery();
}
You need to call ExecuteNonQuery which executes the query against the database.
Always use parameters instead of string concatenation in your queries. It guards against sql injection and ensures you never has issues with strings that contain escape characters.
I did not include any error handling or return messages but do note that you are throwing away all the good stuff in your excetion handler's catch block, you will never know why a query failed after this has executed.
is there something wrong with my codes. I already try another codes but the problem is still the same. I've been solving this error for a couple of weeks now, and i can't figure it out how to solve it. And also I already try some another code but the problem is still the same.
I want to save a multiple row from dataGrid to my database.
here's the codes that i use to save a multiple row
private void button1_Click(object sender, EventArgs e)
{
MySqlConnection conString = new MySqlConnection("datasource = localhost; port = 3306; Initial catalog = dbnewsystem; username = root;password = 1234");
MySqlCommand command1 = new MySqlCommand("INSERT INTO purchaseorder (orNo, ProdNo, Quantity, total)" +
"VALUES(#ORNo,#ProductNo,#quantity,#total )", conString);
command1.Parameters.AddWithValue("#ORNo", dataGridView1.Rows.Count);
command1.Parameters.AddWithValue("#ProductNo", dataGridView1.Rows.Count);
command1.Parameters.AddWithValue("#quantity", dataGridView1.Rows.Count);
command1.Parameters.AddWithValue("#total", textBox6.Text);
conString.Open();
command1.ExecuteNonQuery();
command1.Connection = conString;
conString.Close();
command1.CommandType = CommandType.StoredProcedure;
command1.CommandText = "pos_save";
if (command1.ExecuteNonQuery() == 1)
{
MessageBox.Show("saved");
}
else
{
MessageBox.Show("Sorry Nothing to be Update");
}
conString.Close();
}
change sequence
command1.Connection = conString;
command1.ExecuteNonQuery();
You have implemented wrong sequence:
...
conString.Open(); // Connection opened
command1.ExecuteNonQuery(); // Try executing (fail)
command1.Connection = conString; // Connection assigned
Change to
conString.Open(); // Connection opened
command1.Connection = conString; // Connection assigned
command1.ExecuteNonQuery(); // Try executing (fail)
A better design is
// Wrap IDisposable into using
using (MySqlConnection conString = new MySqlConnection("...")) {
conString.Open();
// Make SQL Readable
string sql =
#"INSERT INTO purchaseorder(
orNo,
ProdNo,
Quantity,
total)
VALUES(
#ORNo,
#ProductNo,
#quantity,
#total)";
// Wrap IDisposable into using
using (MySqlCommand command1 = new MySqlCommand(sql, conString)) {
command1.Parameters.AddWithValue("#ORNo", dataGridView1.Rows.Count);
command1.Parameters.AddWithValue("#ProductNo", dataGridView1.Rows.Count);
command1.Parameters.AddWithValue("#quantity", dataGridView1.Rows.Count);
command1.Parameters.AddWithValue("#total", textBox6.Text);
command1.ExecuteNonQuery();
}
}
I'm trying something out but cant figure it out. So what i'm trying is that if the user inputs something inside txtISN and it already exists inside of the database, the record wont be inserted. I also want a error msg to pop up when a record wasnt inserted and when a record is inserted I want an message to pop up saying that the record was inserted succesfully.
Thanks for the help y'all!
string _connStr = #"Data Source = EJQ7FRN; Initial Catalog = BES; Integrated Security = True";
string _query = "INSERT INTO [BES_S] (ISN,Titel,Name) values (#ISN,#Titel,#Name)";
using (SqlConnection conn = new SqlConnection(_connStr))
{
using (SqlCommand comm = new SqlCommand())
{
comm.Connection = conn;
comm.CommandType = CommandType.Text;
comm.CommandText = _query;
comm.Parameters.AddWithValue("#ISN", txtISN.Text);
comm.Parameters.AddWithValue("#Titel",txtTitel.Text);
comm.Parameters.AddWithValue("#Name", txtName.Text);
try
{
conn.Open();
comm.ExecuteNonQuery();
}
catch (SqlException ex)
{
}
}
}
You need to change your query a bit, but you can use MySql's DUAL keyword to do this:
string _connStr = #"Data Source = EJQ7FRN; Initial Catalog = BES; Integrated Security = True";
string _query = "INSERT INTO [BES_S] (ISN,Titel,Name) ";
_query = _query + " SELECT #ISN, #Titel, #Name FROM DUAL";
_query = _query + " WHERE NOT EXISTS (SELECT ISN WHERE ISN=#ISN)";
using (SqlConnection conn = new SqlConnection(_connStr))
{
using (SqlCommand comm = new SqlCommand())
{
comm.Connection = conn;
comm.CommandType = CommandType.Text;
comm.CommandText = _query;
comm.Parameters.AddWithValue("#ISN", txtISN.Text);
comm.Parameters.AddWithValue("#Titel",txtTitel.Text);
comm.Parameters.AddWithValue("#Name", txtName.Text);
try
{
conn.Open();
comm.ExecuteNonQuery();
}
catch (SqlException ex)
{
}
}
}
DUAL is like a dummy table that you can use to SELECT from.
Let the database take care of this using a unique constraint/index:
alter table bes_s add constraint unq_bes_ISN unique (ISN);
This will cause the database to generate an error if a duplicate ISN is inserted. You can put one or more columns for the unique constraint (in case this single column is not the exact definition of uniqueness).
I want to perform 2 queries in one button click. I tried the
string query = "first query";
query+="second query";
But this didn't work it shows error.
I have now created 2 separate connections like below:
try
{
SqlConnection conn1 = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnectionStringDatabase"].ConnectionString);
//open connection with database
conn1.Open();
//query to select all users with teh given username
SqlCommand com1 = new SqlCommand("insert into artikulli (tema,abstrakti, kategoria_id, keywords ) values (#tema, #abstrakti, #kategoria, #keywords)", conn1);
// comand.Parameters.AddWithValue("#id", iD);
com1.Parameters.AddWithValue("#tema", InputTitle.Value);
com1.Parameters.AddWithValue("#abstrakti", TextareaAbstract.Value);
com1.Parameters.AddWithValue("#kategoria", DropdownCategory.Value);
com1.Parameters.AddWithValue("#keywords", InputTags.Value);
//execute queries
com1.ExecuteNonQuery();
conn1.Close();
if (FileUploadArtikull.HasFile)
{
int filesize = FileUploadArtikull.PostedFile.ContentLength;
if (filesize > 4194304)
{
ScriptManager.RegisterStartupScript(this, this.GetType(), "popup", "alert('Maximumi i madhesise eshte 4MB');", true);
}
else
{
string filename = "artikuj/" + Path.GetFileName(FileUploadArtikull.PostedFile.FileName);
SqlConnection conn2 = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnectionStringDatabase"].ConnectionString);
SqlCommand com2 = new SqlCommand("insert into artikulli(path) values ('" + filename + "')", conn2);
//open connection with database
conn2.Open();
com2.ExecuteNonQuery();
FileUploadArtikull.SaveAs(Server.MapPath("~/artikuj\\" + FileUploadArtikull.FileName));
Response.Redirect("dashboard.aspx");
}
}
else
{
ScriptManager.RegisterStartupScript(this, this.GetType(), "popup", "alert('Ju nuk keni perzgjedhur asnje file');", true);
}
}
But the problem is that only the second query is performed and the firs is saved as null in database
In your case, there is no reason to open two connections. In addition, the C# language has evolved, so I recommend using the power given by the new language constructs (using, var).
Here is an improved version that should work assuming that the values you bind to your parameters are valid:
try
{
using(var connection = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnectionStringDatabase"].ConnectionString))
{
//open connection with database
connection.Open();
//query to select all users with teh given username
using(var command1 = new SqlCommand("insert into artikulli (tema,abstrakti, kategoria_id, keywords ) values (#tema, #abstrakti, #kategoria, #keywords)", connection))
{
command1.Parameters.AddWithValue("#tema", InputTitle.Value);
command1.Parameters.AddWithValue("#abstrakti", TextareaAbstract.Value);
command1.Parameters.AddWithValue("#kategoria", DropdownCategory.Value);
command1.Parameters.AddWithValue("#keywords", InputTags.Value);
//execute first query
command1.ExecuteNonQuery();
}
//build second query
string filename = "artikuj/" + Path.GetFileName(FileUploadArtikull.PostedFile.FileName);
using(SqlCommand command2 = new SqlCommand("insert into artikulli(path) values (#filename)", connection))
{
//add parameters
command2.Parameters.AddWithValue("#filename", filename);
//execute second query
command2.ExecuteNonQuery();
}
}
}
//TODO: add some exception handling
//simply wrapping code in a try block has no effect without a catch/finally
Try below code, No need to open the connection twice
string query1 = "insert into artikulli (tema,abstrakti, kategoria_id, keywords ) values (#tema, #abstrakti, #kategoria, #keywords)";
SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnectionStringDatabase"].ConnectionString);
SqlCommand com1= new SqlCommand(query1, conn);
com1.Parameters.AddWithValue("#tema", InputTitle.Value);
com1.Parameters.AddWithValue("#abstrakti", TextareaAbstract.Value);
com1.Parameters.AddWithValue("#kategoria", DropdownCategory.Value);
com1.Parameters.AddWithValue("#keywords", InputTags.Value);
string query2 = "insert into artikulli(path) values ('" + filename + "')", conn);
comm.ExecuteNonQuery();
comm.CommandText = query2;
comm.ExecuteScalar();
In my code below, the cmdquery works but the hrquery does not. How do I get another query to populate a grid view? Do I need to establish a new connection or use the same connection? Can you guys help me? I'm new to C# and asp. Here's some spaghetti code I put together. It may all be wrong so if you have a better way of doing this feel free to share.
if (Badge != String.Empty)
{
string cmdquery = "SELECT * from Employees WHERE Badge ='" + Badge + "'";
string hrquery = "SELECT CLOCK_IN_TIME, CLOCK_OUT_TIME FROM CLOCK_HISTORY WHERE Badge ='" + Badge + "'";
OracleCommand cmd = new OracleCommand(cmdquery);
cmd.Connection = conn;
cmd.CommandType = CommandType.Text;
conn.Open();
OracleDataReader reader = cmd.ExecuteReader();
while (reader.Read())
{
this.xUserNameLabel.Text += reader["EMPLOYEE_NAME"];
this.xDepartmentLabel.Text += reader["REPORT_DEPARTMENT"];
}
OracleCommand Hr = new OracleCommand(hrquery);
Hr.Connection = conn;
Hr.CommandType = CommandType.Text;
OracleDataReader read = Hr.ExecuteReader();
while (read.Read())
{
xHoursGridView.DataSource = hrquery;
xHoursGridView.DataBind();
}
}
conn.Close();
Your data access code should generally look like this:
string sql = "SELECT * FROM Employee e INNER JOIN Clock_History c ON c.Badge = e.Badge WHERE e.Badge = #BadgeID";
using (var cn = new OracleConnection("your connection string here"))
using (var cmd = new OracleCommand(sql, cn))
{
cmd.Parameters.Add("#BadgeID", OracleDbType.Int).Value = Badge;
cn.Open();
xHoursGridView.DataSource = cmd.ExecuteReader();
xHoursGridView.DataBind();
}
Note that this is just the general template. You'll want to tweak it some for your exact needs. The important things to take from this are the using blocks to properly create and dispose your connection object and the parameter to protect against sql injection.
As for the connection question, there are exceptions but you can typically only use a connection for one active result set at a time. So you could reuse your same conn object from your original code, but only after you've completely finished with it from the previous command. It is also okay to open up two connections if you need them. The best option, though, is to combine related queries into single sql statement when possible.
I'm not even going to get into how you should be using usings and methods :p
if (Badge != String.Empty)
{
string cmdquery = "SELECT * from Employees WHERE Badge ='" + Badge + "'";
string hrquery = "SELECT CLOCK_IN_TIME, CLOCK_OUT_TIME FROM CLOCK_HISTORY WHERE Badge ='" + Badge + "'";
OracleCommand cmd = new OracleCommand(cmdquery);
cmd.Connection = conn;
cmd.CommandType = CommandType.Text;
conn.Open();
OracleDataReader reader = cmd.ExecuteReader();
while (reader.Read())
{
this.xUserNameLabel.Text += reader["EMPLOYEE_NAME"];
this.xDepartmentLabel.Text += reader["REPORT_DEPARTMENT"];
}
OracleCommand Hr = new OracleCommand(hrquery);
Hr.Connection = conn;
Hr.CommandType = CommandType.Text;
OracleDataReader read = Hr.ExecuteReader();
//What's this next line? Setting the datasource automatically
// moves through the data.
//while (read.Read())
//{
//I changed this to "read", which is the
//datareader you just created.
xHoursGridView.DataSource = read;
xHoursGridView.DataBind();
//}
}
conn.Close();