How to load data from PostgreSQL to RichTextBox? - c#

I'm trying to convert data to RichTextBox but still can't do it. Below is my code. My data test and have data, now just read it into RichTextBox.
private void btnConvert_Click(object sender, EventArgs e)
{
ListViewItem selectedComune = lvResultCommune.SelectedItems[0];
string selectedCommuneId = selectedComune.Text;
if (selectedCommuneId != null)
{
NpgsqlDataAdapter adapter = new NpgsqlDataAdapter();
NpgsqlCommand cmd = new NpgsqlCommand("SELECT ST_AsText(geom) as geometry FROM hanhchinhxa where id_4 = " + selectedCommuneId , conn);
adapter.SelectCommand = cmd;
cmd.Connection = conn;
DataTable data = new DataTable();
adapter.Fill(data);
richTextBox.Text = data.ToString();
}
else
{
throw new Exception("\n" + "Geometry illegal !!");
}
}

I found the answer by myself !
richTextBox.Text = data.Rows[0].ItemArray[0].ToString();

Related

How to get data from SQL and write it in textbox?

I need a help.
I searched and I tried a lot but I am too bad to make it work on my project by myself.
This is code for button-Seek. I want to make Seek-button to fill textbox by respective data.
private void SeekClick(object sender, EventArgs e)
{
if (TBCusNumber.Text != "")
{
string Number = TBCusNumber.Text;
var Conn = new SqlConnection();
Conn.ConnectionString = ConfigurationManager.ConnectionStrings["WindowsFormsApp1.Properties.Settings.DataBase"].ConnectionString;
var Cmd = new SqlCommand();
Cmd.Connection = Conn;
Cmd.CommandText = "SELECT * FROM CustomerList WHERE CustomerNumber = " + Number;
var DataAdapter = new SqlDataAdapter(Cmd);
DataSet DataSet = new DataSet();
DataAdapter.Fill(DataSet, "CustomerList");
CusView.DataSource = DataSet;
CusView.DataMember = "CustomerList";
}
}
And This is the data table.
This is what happens when I put 3 in the text box and press Seek-button.
So here, I want all text boxes to be filled by the data which I searched.
You will get only one row for the query right?
So give like that,
txtFirstName.Text = DataSet.Tables[0].Rows[0]["FirstName"].ToString();
txtLasttName.Text = DataSet.Tables[0].Rows[0]["LastName"].ToString();
Like this you need to assign the values to the respective text boxes.
There are three problem need to fix.
You forget to open the connection with DB,add Conn.Open(); before you excute sql command.
You need to add parameter to prevention SQL Injection
Please use using it will help you to use external resources to return the memory.
when the DataSet be filled you can get the data then fill in textbox
You can follow like this.
private void SeekClick(object sender, EventArgs e)
{
if (TBCusNumber.Text != "")
{
string Number = TBCusNumber.Text;
using (var Conn = new SqlConnection())
{
Conn.ConnectionString = ConfigurationManager.ConnectionStrings["WindowsFormsApp1.Properties.Settings.DataBase"].ConnectionString;
using (var Cmd = new SqlCommand())
{
Cmd.Connection = Conn;
Cmd.CommandText = "SELECT * FROM CustomerList WHERE CustomerNumber = #Number";
Cmd.Parameters.AddWithValue("#Number", Number);
//You miss to add Conn.Open()
Conn.Open();
using (var DataAdapter = new SqlDataAdapter(Cmd))
{
DataSet DataSet = new DataSet();
DataAdapter.Fill(DataSet, "CustomerList");
CusView.DataSource = DataSet;
CusView.DataMember = "CustomerList";
//when the DataSet be filled you can get the data then fill in textbox
txt_firstName.Text = DataSet.Tables[0].Rows[0]["FirstName"].ToString();
}
}
}
}
}

changing value of cell on condition in gridview - c#

I have fetched the data from SQL server to datagridview but I don't know how to change the cell value. I have to change the fetched value 1 and 0 to available and unavailable. here is my code for fetching data ... please help.
private void btnsearch_Click(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection("server = 192.168.100.6;Database=sms;UID=sa;Password=1234;");
SqlCommand cmd = new SqlCommand("Select id as 'Book ID',name as 'Name' , status as 'Status' from book where Name = #name", con);
cmd.Parameters.AddWithValue("#name", txtFirstName.Text);
try
{
SqlDataAdapter da = new SqlDataAdapter();
da.SelectCommand = cmd;
DataTable dt = new DataTable();
da.Fill(dt);
BindingSource bsource = new BindingSource();
bsource.DataSource = dt;
dataGridView1.DataSource = bsource;
}
catch (Exception ec)
{
MessageBox.Show(ec.Message);
}
// chage_value();
dataGridView1.Show();
}
}
Please find below answer
private void btnsearch_Click(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection("server = 192.168.100.6;Database=sms;UID=sa;Password=1234;");
string sSql=#"Select id as 'Book ID',name as 'Name' ,
Case when status=0 then 'unavailable' else 'available '
End as 'Status' from
book where Name ='"+txtFirstName.Text +"'"
SqlCommand cmd = new SqlCommand(sSql, con);
try
{
SqlDataAdapter da = new SqlDataAdapter();
da.SelectCommand = cmd;
DataTable dt = new DataTable();
da.Fill(dt);
dataGridView1.DataSource = dt;
}
catch (Exception ec)
{
MessageBox.Show(ec.Message);
}
// chage_value();
dataGridView1.Show();
}
}
First of all, try to store your queries in variables. This will help you in the long run. Also, it is good practise to check whether you are connected or not before trying to send a query away to the server. It is important to remeber that when you fetch data from your server, it will most likely be seen as a string, so if you want to compare it as a number, you need to convert it first.
What you could do is something similar to what i've written below. You count the amount of answers your query returns, then loop through them and check whether they are 0 or 1. Then just replace the value with Avaliable or Unavaliable.
if (dbCon.IsConnect()){
MySqlCommand idCmd = new MySqlCommand("Select * from " + da.DataGridView1.Text, dbCon.Connection);
using (MySqlDataReader reader = idCmd.ExecuteReader()){
// List<string> stringArray = new List<string>(); // you could use this string array to compare them, if you like this approach more.
while (reader.Read()){
var checkStatus= reader["Status"].ToString();
Console.WriteLine("Status: " + checkStatus.Split(' ').Count()); //checks how many items you've got.
foreach (var item in checkStatus.Split(' ').Select(x => x.Trim()).Where(x => !string.IsNullOrWhiteSpace(x)).ToArray()){
var item2 = 0.0; // your 0 or 1 for avaliable or unavaliable..
try{
item2 = double.Parse(item.ToString());
if(strcmp(item2,'0') == 1){ //assuming you only have 0's and 1's.
item2 = "unavaliable";
}else{
item2 = "avaliable";
}
}
catch (Exception){
//do what you want
}
Console.WriteLine("item: " + item2);
}
}
dbCon.Close();
}
}
return //what you want;
}

Not getting any row data from database using c# asp.net.

I can not get any row data from database using c# asp.net.I am trying to fetch one row data from my DB but it is not returning any row.I am using 3-tire architecture for this and i am explaining my code below.
index.aspx.cs:
protected void userLogin_Click(object sender, EventArgs e)
{
if (loginemail.Text.Trim().Length > 0 && loginpass.Text.Trim().Length >= 6)
{
objUserBO.email_id = loginemail.Text.Trim();
objUserBO.password = loginpass.Text.Trim();
DataTable dt= objUserBL.getUserDetails(objUserBO);
Response.Write(dt.Rows.Count);
}
}
userBL.cs:
public DataTable getUserDetails(userBO objUserBO)
{
userDL objUserDL = new userDL();
try
{
DataTable dt = objUserDL.getUserDetails(objUserBO);
return dt;
}
catch (Exception e)
{
throw e;
}
}
userDL.cs:
public DataTable getUserDetails(userBO objUserBO)
{
SqlConnection con = new SqlConnection(CmVar.convar);
try
{
con.Open();
DataTable dt = new DataTable();
string sql = "SELECT * from T_User_Master WHERE User_Email_ID= ' " + objUserBO.email_id + "'";
SqlCommand cmd = new SqlCommand(sql, con);
SqlDataAdapter objadp = new SqlDataAdapter(cmd);
objadp.Fill(dt);
con.Close();
return dt;
}
catch(Exception e)
{
throw e;
}
}
When i am checking the output of Response.Write(dt.Rows.Count);,it is showing 0.So please help me to resolve this issue.
It looks like your your query string has a redundant space between ' and " mark. That might be causing all the trouble as your email gets space in front.
It is by all means better to add parameters to your query with use of SqlConnection.Parameters property.
string sql = "SELECT * from T_User_Master WHERE User_Email_ID=#userID";
SqlCommand cmd = new SqlCommand(sql, con);
cmd.Parameters.Add("#userID", SqlDbType.NVarChar);
cmd.Parameters["#userID"].Value = objUserBO.email_id;

Update sql database using dataset

I need some help to complete this. I have searched and tried several ways but is not enetring in my head yet. It is not homework! I am a self learner.
I managed to populate a grid selecting the table from a dropdown:
private void radDropDownList1_SelectedIndexChanged(object sender, Telerik.WinControls.UI.Data.PositionChangedEventArgs e)
{
if (radDropDownList1.SelectedIndex > 0)
{
radGridView1.Visible = true;
label8.Text = radDropDownList1.SelectedValue.ToString();
DataTable dt = new DataTable();
var selectedTable = radDropDownList1.SelectedValue; //Pass in the table name
string query = #"SELECT * FROM " + selectedTable;
using (var cn = new SqlConnection(connString))
{
cn.Open();
try
{
SqlCommand cmd = new SqlCommand(query, cn);
using (var da = new SqlDataAdapter(cmd))
{
da.Fill(dt);
}
}
catch (SqlException ex)
{
//MessageBox.Show(ex.StackTrace);
}
}
radGridView1.DataSource = dt;
}
Now I am trying to write the event to update the sql table using the grid as datasource:
private void radGridView1_CellEndEdit(object sender, Telerik.WinControls.UI.GridViewCellEventArgs e)
{
DataTable dt = (DataTable)radGridView1.DataSource;
DataSet ds = new DataSet();
ds.Tables[0] = dt;
try
{
//**I am lost here!**
}
catch
{
}
}
Could you please help? How can I now update the sql table?
I don't really like the way you are managing the updates but... this code here will send an update statement:
using (var cn = new SqlConnection(connString))
{
cn.Open();
try
{
SqlCommand cmd = new SqlCommand("UPDATE YourTable SET Column = #Parm1 WHERE Col = #Parm2", cn);
var parm1 = cmd.CreateParameter("Parm1");
parm1.Value = "SomeValue";
var parm2 = cmd.CreateParameter("Parm2");
parm2.Value = "SomeOtherValue";
cmd.Parameters.Add(parm1);
cmd.Parameters.Add(parm2);
int rowsAffected = cmd.ExecuteNonQuery();
}
catch (SqlException ex)
{
//MessageBox.Show(ex.StackTrace);
}
}

SqlDataAdapter.Update or SqlCommandBuilder not working

I have a form with a datagrid, which is populated wih data from a sqlserver database. The datagrid populates fine but I am having trouble posting back the changes made by the user, to the table in the sql database. My forms code is as follows:
public partial class frmTimesheet : Form
{
private DataTable tableTS = new DataTable();
private SqlDataAdapter adapter = new SqlDataAdapter();
private int currentTSID = 0;
public frmTimesheet()
{
InitializeComponent();
}
private void frmTimesheet_Load(object sender, EventArgs e)
{
string strUser = cUser.currentUser;
cMyDate cD = new cMyDate(DateTime.Now.ToString());
DateTime date = cD.GetDate();
txtDate.Text = date.ToString();
cboTSUser.DataSource = cUser.GetListOfUsers("active");
cboTSUser.DisplayMember = "UserID";
cboTSUser.Text = strUser;
CheckForTimeSheet();
PopulateTimeSheet();
}
private void CheckForTimeSheet()
{
string strUser = cboTSUser.Text;
cMyDate cD = new cMyDate(txtDate.Text);
DateTime date = cD.GetDate();
int newTSID = cTimesheet.TimeSheetExists(strUser, date);
if (newTSID != this.currentTSID)
{
tableTS.Clear();
if (newTSID == 0)
{
MessageBox.Show("Create TimeSheet");
}
else
{
this.currentTSID = newTSID;
}
}
}
private void PopulateTimeSheet()
{
try
{
string sqlText = "SELECT EntryID, CaseNo, ChargeCode, StartTime, FinishTime, Units " +
"FROM tblTimesheetEntries " +
"WHERE TSID = " + this.currentTSID + ";";
SqlConnection linkToDB = new SqlConnection(cConnectionString.BuildConnectionString());
SqlCommand sqlCom = new SqlCommand(sqlText, linkToDB);
SqlDataAdapter adapter = new SqlDataAdapter(sqlCom);
adapter.SelectCommand = sqlCom;
SqlCommandBuilder builder = new SqlCommandBuilder(adapter);
adapter.Fill(tableTS);
dataTimesheet.DataSource = tableTS;
}
catch (Exception eX)
{
string eM = "Error Populating Timesheet";
cError err = new cError(eX, eM);
MessageBox.Show(eM + Environment.NewLine + eX.Message);
}
}
private void txtDate_Leave(object sender, EventArgs e)
{
CheckForTimeSheet();
PopulateTimeSheet();
}
private void cboTSUser_DropDownClosed(object sender, EventArgs e)
{
CheckForTimeSheet();
PopulateTimeSheet();
}
private void dataTimesheet_CellValueChanged(object sender, DataGridViewCellEventArgs e)
{
try
{
adapter.Update(tableTS);
}
catch (Exception eX)
{
string eM = "Error on frmTimesheet, dataTimesheet_CellValueChanged";
cError err = new cError(eX, eM);
MessageBox.Show(eM + Environment.NewLine + eX.Message);
}
}
}
No exception occurs, and when I step through the issue seems to be with the SqlCommandBuilder which does NOT build the INSERT / UPDATE / DELETE commands based on my gien SELECT command.
Can anyone see what I am doing wrong?
What am I missing?
You need to set the UpdateCommand instead of SelectCommand on update:
SqlDataAdapter adapter = new SqlDataAdapter();
SqlCommandBuilder sqlBld = new SqlCommandBuilder(adapter)
adapter.UpdateCommand = sqlBld.GetUpdateCommand() ;
The question is old, but the provided answer by#Anurag Ranjhan need to be corrected.
You need not to write the line:
adapter.UpdateCommand = sqlBld.GetUpdateCommand() ;
and enough to write:
SqlDataAdapter adapter = new SqlDataAdapter();
SqlCommandBuilder sqlBld = new SqlCommandBuilder(adapter)
//remove the next line
//adapter.UpdateCommand = sqlBld.GetUpdateCommand() ;
The Sql update/insert/delete commands are auto generated based on this line
SqlCommandBuilder sqlBld = new SqlCommandBuilder(adapter)
You can find the generated update sql by executing the line:
sqlBld.GetUpdateCommand().CommandText;
See the example How To Update a SQL Server Database by Using the SqlDataAdapter Object in Visual C# .NET
The problem said by OP can be checked by reviewing the Sql Statement sent by the client in SQl Server Profiler.

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