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Sum hours from different formatted dates. C#

I have a problem. I need to sum hours worked in an office in a code. The dates i get from SQL server thats no problem but i have different formats. For example: 2019. 09. 23. 14:54:23, 2019.09.23 14:54:23 or 2019-09-23 14:54:23; And i want to sum hours worked in result. No matter the year. Heres the example:
try
{
string betölt = "SELECT * from munkaorak where";
if (cbTech.Text != "")
{
betölt += " Munkaszam='" + cbMunka.Text + "' AND Részfolyamat='" + cbRész.Text + "' AND TechKod='" + cbTech.Text + "'";
}
else if (cbRész.Text != "")
{
betölt += " Munkaszam='" + cbMunka.Text + "' AND Részfolyamat='" + cbRész.Text + "'";
}
else if(cbMunka.Text !="")
{
betölt += " Munkaszam='" + cbMunka.Text + "'";
}
betölt += " order by ID DESC";
MySqlCommand name = new MySqlCommand(betölt, kapcsolat);
kapcsolat.Open();
olvasó = name.ExecuteReader();
int összora = 0;
if (olvasó.HasRows)
{
while (olvasó.Read())
{
if (olvasó.GetString(7) != "Befejezés: ")
{
string[] aha = olvasó.GetString(6).Split(' ');
string kezdes = aha[4];
string[] kezd = kezdes.Split(':');
int kezdoido = Convert.ToInt32(kezd[0]) * 60 * 60 + Convert.ToInt32(kezd[1]) * 60 + Convert.ToInt32(kezd[2]);
int befejezoido = 0;
string aha22 = "";
if (olvasó.GetString(7).IndexOf('-') >= 0)
{
string[] aha2 = olvasó.GetString(7).Split(' ');
string befejezes = aha2[1];
string[] bef = befejezes.Split(':');
aha22 = aha2[0].Split('-')[2];
befejezoido = Convert.ToInt32(bef[0]) * 60 * 60 + Convert.ToInt32(bef[1]) * 60 + Convert.ToInt32(bef[2]);
}
else
{
string[] aha2 = olvasó.GetString(7).Split(' ');
string befejezes = aha2[4];
string[] bef = befejezes.Split(':');
aha22 = aha2[3];
befejezoido = Convert.ToInt32(bef[0]) * 60 * 60 + Convert.ToInt32(bef[1]) * 60 + Convert.ToInt32(bef[2]);
}
string dolgozott = "";
if (aha[3].Replace(".", "") == aha22.Replace(".", ""))
{
dolgozott = mpbolora(befejezoido - kezdoido);
összora += befejezoido - kezdoido;
}
else
{
dolgozott = mpbolora((86400 - kezdoido) + befejezoido);
összora += (86400 - kezdoido) + befejezoido;
}
string validalo = "";
try
{
string[] validal = olvasó.GetString(9).Split(' ');
validalo = validal[0] + " " + validal[1] + " " + validal[2] + validal[3] + validal[4] + " " + validal[5];
}
catch
{
validalo = olvasó.GetString(9);
}
string munkafolyamat = olvasó.GetString(3) + "-" + olvasó.GetString(4) + "-" + olvasó.GetString(5);
string[] sorok = { olvasó.GetString(2), dolgozott, olvasó.GetString(6).Replace("Kezdés: ", ""), olvasó.GetString(7).Replace("Befejezés: ", ""), olvasó.GetString(8), validalo, munkafolyamat };
var lv = new ListViewItem(sorok);
lvStat.Items.Add(lv);
}
}
}
else
{
kapcsolat.Close();
MessageBox.Show("Nincs adat!", "Figyelem");
}
kapcsolat.Close();
lblÖssz.Text = "Összesen ledolgozott órák: " + mpbolora(összora);
}
catch (Exception a)
{
MessageBox.Show(a.Message);
kapcsolat.Close();
}
kapcsolat.Close();
It worked but when different formats appeared its not working because '-' or spaces. Please help!

In C#, there is a bunch of methods provided to convert strings that contain date times in many formats into a unified DateTime object. These methods can recognize quite a few standard date time formats, and if yours differ from them, you can even provide your own.
DateTime.Parse() - Converts a string to a DateTime object. If operation fails, it'll thrown an exception.
DateTime.TryParse() - Converts a string to a DateTime object only if possible. Returns true if successful, and false if it fails.
DateTime.TryParseExact() - Converts a string that is in the specified format into a DateTime object. Returns true if successful, and false otherwise.
In your case, you can use DateTime.TryParse() (which is recommended over simply using DateTime.Parse() unless you're absolutely sure the format is correct) like so:
var dtStr1 = " 2019. 09. 23. 14:54:23";
var dtStr2 = "2019.09.23 14:54:23";
var dtStr3 = "2019-09-23 14:54:23";
DateTime.TryParse(dtStr1, out DateTime dt1);
DateTime.TryParse(dtStr2, out DateTime dt2);
DateTime.TryParse(dtStr3, out DateTime dt3);
Once converted to a DateTime object, it no longer has a format associated with it. It's a structure, and hence only has member variables and methods. So to calculate total hours etc. you can use provided methods.
Say you want to calculate time between day's work start and end. You can convert those into DateTime objects, then subtract one from the others which will give you a TimeSpam object.
var dtStrStart = "2019.09.23 08:23:12";
var dtStrEnd = "2019.09.23 16:17:28";
DateTime.TryParse(dtStrStart, out DateTime dtStart);
DateTime.TryParse(dtStrEnd, out DateTime dtEnd);
var diff = dtEnd - dtStart;
Now the TimeSpan object, which is diff here, will give you a bunch of properties with difference in hours, minutes etc.
The TimeSpan.Days, TimeSpan.Minutes etc will give you the time in days, minutes etc.
Console.WriteLine(diff.Days);
Console.WriteLine(diff.Hours);
Console.WriteLine(diff.Minutes);
Console.WriteLine(diff.Seconds);
Console.WriteLine(diff.Milliseconds);
Output:
0
7
54
16
0
The TimeSpan.TotalMinutes etc will give you the entire time period in respective units.
Console.WriteLine(diff.TotalDays);
Console.WriteLine(diff.TotalHours);
Console.WriteLine(diff.TotalMinutes);
Console.WriteLine(diff.TotalSeconds);
Console.WriteLine(diff.TotalMilliseconds);
Output:
0.329351851851852
7.90444444444444
474.266666666667
28456
28456000
And conversely, when you're storing data in the database, you must again use a standard format, such as datetime or datetime2. It's advised you use datetime2, more info here.

Your code should look more like this:
try
{
MySqlCommand name = new MySqlCommand("SELECT * from munkaorak WHERE Munkaszam=#m", kapcsolat);
name.Parameters.AddWithValue("#m", cbMunka.Text);
if (cbRész.Text != "")
{
name.CommandText += " AND Részfolyamat=#r";
name.Parameters.AddWithValue("#r", cbRész.Text);
}
if (cbTech.Text != "")
{
name.CommandText += " AND TechKod=#t";
name.Parameters.AddWithValue("#t", cbTech.Text);
}
name.CommandText += " order by ID DESC"; //is it really necessary?
MySqlDataAdapter da = new MySqlDataAdapter(name);
DataTable dt = new DataTable();
da.Fill(dt);
foreach(DataRow ro in dt.Rows){
string fromStr = ro["YOUR_FROM_DATE_COLUMN_NAME"].ToString();
//cope with dates in varying formats
//by replacing all non-numeric chars with nothing
fromStr = Regex.Replace(fromStr, #"[^0-9]", "");
//now our dates of [2019. 09. 23. 14:54:23], [2019.09.23 14:54:23] or [2019-09-23 14:54:23]
//just become 20190923145423
DateTime fromDt = DateTime.ParseExact(fromStr, "yyyyMMddHHmmss", CultureInfo.InvariantCulture);
string toStr = ro["YOUR_TO_DATE_COLUMN_NAME"].ToString();
toStr = Regex.Replace(toStr, #"[^0-9]", "");
DateTime toDt = DateTime.ParseExact(toStr, "yyyyMMddHHmmss", CultureInfo.InvariantCulture);
//total hours worked
(toDt - fromDt).TotalHours;
}
}
Hopefully that looks a lot simpler
Here you see no..:
Risky SQL injection hack possibility - don't concatenate values into your SQL, ever. Always concatenate a parameter in and then give a value to the parameter. Always
Difficult to read, lengthy string concatenation - looks terrible, always avoid it if you can
DB Connection opening and closing - micromanaging the database connection isn't necessary when using a dataadapter because it opens and closes for you
DataReader code full of magic numbers - GetString(7), hmmm.. was that the time in or time out? GetInt(4) - was it the age? The year? Here we get rid of all the datareader GetXX calls with their column ordinals and fill a DataTable (something like a 2D array) with rows that can be indexed by string names. It's still not as good as it can be (strongly typed DataTables are better) but it's a huge leap better than filling code with magic numbers, and working with everything in the most obscure, weakly typed way possible
Awkward time handling - it's gone in favour of Date parsing, because pulling strings to bits number by number, converting them to int, multiplying them by seconds and hours so they can be manipulated is tedious and hard to read - do away with it all by parsing these strings to the data types that they should have been stored as in the first place; you need to record the date and times that things happen at. Try your best to get that DB converted so these things are stored properly, and until then convert your strings to DateTime
Diffing dates using seconds: utilising TimeSpan calculations means no need to convert things to seconds, do crude math, drop all notions of time zones, or daylight savings changes etc; by using dates subtracted from each other you get a time period between those dates that takes things like daylight saving clock changes into account. Or even the ability to have one date that is tomorrow, or X days into the future. Might not matter for this app, but one day it could..
If you have MySQL 8 you can do the regex replace in the DB. Could even get the DB to diff and sum the dates.. We can't really make any recommendations on this point though because we don't know the column names

cant store an HTML page when ncarchar(max) is capped at 4000 characters

To put it simple, how to increase the cap of nvarchar(MAX) to actually hold 280MB of text and not just 8000MB (correct me if I'm wrong)?
So, for my finals project I'm making a web-crawler for a client that wants its own customized search engine for their library website, but my problem arises when i try to store the infomation that the crawlers retrieve.
Specifically the problem I have is that even tho I set the column "HTML" to nvarchar(MAX), which should be able to hold 2GB of data, it wont save any infomation to it, in this case 280MB, cause it's too long.
I did try shortening the length of the text to be saved and when I made it sufficiently short enough it finally agreed to save the data, so from what I can understand it's capped.
EDIT: Code examples as requested
page container class:
public class Page
{
public int ID = -1;
public String URL;
public String HeadLine;
public List<String> Tags;
public String Description;
public String HTML;
public DateTime lastUpdate;
}
Code snippet when crawler saves the page that it has retrieved:
//Save Page content to Database
Page page = new Page();
page.URL = url;
page.HeadLine = headline;
page.Tags = tags.Split(',').Where(s => !string.IsNullOrWhiteSpace(s)).ToList();
page.Description = description;
page.HTML = HTML;
page.lastUpdate = DateTime.Today;
new DBpage(Settings.instance.DBaddress,
Settings.instance.DBname).SavePage(page);
Method used for storing the data:
public void SavePage(Page page) {
String SqlString = "";
//Check is a page by the given URL already exists in the database and assign the SQL string acordingly
Page foundPage = GetPage(page.URL);
if(foundPage == null) {
SqlString = "INSERT INTO WebContent " +
"VALUES (#URL, #HeadLine, #Tags, #Description, #HTML, #LastUpdate)";
}
else {
SqlString = "UPDATE WebContent " +
"SET URL = #URL, HeadLine = #HeadLine, Tags = #Tags, Description = #Description, HTML = #HTML, LastUpdate = #LastUpdate " +
//"SET URL = '" + page.URL + "', HeadLine = '" + page.HeadLine + "', Tags = '" + String.Join(",", page.Tags) + "', Description = '" + page.Description + "', HTML = '" + page.HTML.Replace("'", "''") + "', LastUpdate = " + page.lastUpdate + " " +
"WHERE ID = " + foundPage.ID;
}
//Assign all variables and execute the SQL
try {
using(DBaccess db = new DBaccess(dblocation, dbname)) {
String html = page.HTML.Replace("'", "''"); //Replace all single quotes with double "single quotes" to escape the first single quote.
SqlCommand sqlCmd = db.GetSqlCommand(SqlString);
sqlCmd.Parameters.AddWithValue("#URL", page.URL);
sqlCmd.Parameters.AddWithValue("#HeadLine", page.HeadLine);
sqlCmd.Parameters.AddWithValue("#Tags", String.Join(",", page.Tags));
sqlCmd.Parameters.AddWithValue("#Description", page.Description);
sqlCmd.Parameters.AddWithValue("#HTML", html);
sqlCmd.Parameters.AddWithValue("#LastUpdate", page.lastUpdate);
sqlCmd.ExecuteNonQuery();
}
}
catch(SqlException e) {
Console.WriteLine(e.Message);
}
}
The unfortunate result that puzzles me:

nvarchar(max) type does allow to store up to 2GB of data. For nvarchar it means about 1 billion characters, because N types store text in 2-bytes per character unicode.
nvarchar [ ( n | max ) ]
Variable-length Unicode string data. n defines the string length
and can be a value from 1 through 4,000. max indicates that the
maximum storage size is 2^30-1 characters. The maximum storage size in
bytes is 2 GB. The actual storage size, in bytes, is two times the
number of characters entered + 2 bytes.
Most likely your problem is somewhere in the procedure that tries to INSERT such large text. The first thing that comes to mind is some timeout. It will take a while to upload 280MB of data to the server, so examine the details of failure (look through the error messages and exceptions) to gather clues of what is going wrong.
Few things to check:
Double check the type of the HTML column in the database.
Maybe SSMS doesn't display the long value correctly. Try to run
SELECT LEN(HTML) FROM YourTable
to verify the length of the stored string.
Overall, just step through the code in the debugger and verify that all variables have expected values.

Unable to convert MySQL.DateTime to System.DateTime with 0000-00-00 00:00:00 values

I am working on a C# project and I am facing an issue. The program allows the user to connect to a MySQL database and retrieve information from each selected table and write the data out to a file. The problem is because I have no idea what the schema is going to be like or what values its going to contain.
If the timestamp column contains the date 0000-00-00 00:00:00 I get the conversion error and no matter what I try it never works. I've tried converting to a string I've tried converting to a DateTime but I always get the error.
Below is how I am currently trying to get the data:
using (ConnectMySQLDB db = new ConnectMySQLDB(databaseSettings))
{
string query = string.Format("SELECT * FROM {0}.{1}", database, table);
Console.WriteLine("Query: {0}", query);
using (MySqlCommand cmd = new MySqlCommand(query, db.conn))
{
using (MySqlDataReader reader = cmd.ExecuteReader())
{
int i = 1;
while (reader.Read())
{
Console.WriteLine("ID: {0}", i);
fieldsAndValues = new Dictionary<string, string>();
foreach (ColumnDataTypes fieldAndType in fieldsAndTypes)
{
Console.WriteLine("Column: {0} Type: {1}", fieldAndType.field, fieldAndType.dataType);
string formattedValue = "";
if (fieldAndType.dataType == "timestamp")
{
DateTime date = DateTime.Parse(reader.GetDateTime(fieldAndType.field).ToString());
formattedValue = date.ToString("yyyyMMdd");
}
else
{
formattedValue = getDBFormattedValue(reader.GetString(fieldAndType.field), fieldAndType.dataType);
fieldsAndValues.Add(fieldAndType.field, formattedValue);
}
}
rows.Add(fieldsAndValues);
i++;
}
}
}
}
I also have added the allow zero date and convertzerodate to null option in the connector string as follows:
connString = "server=" + server + ";uid=" + username + ";pwd=" + password + ";port=" + port + ";Allow Zero Datetime=true;zeroDateTimeBehavior=convertToNull;Convert Zero Datetime=true";

Looking at this documentation, it looks like you're specifying two contradictory options (AllowZeroDateTime=true and ConvertZeroDateTime=true) and one which appears not to be listed (ZeroDateTimeBehavior=ConvertToNull).
I suggest that unless you have actual data which is DateTime.MinValue which you don't want to mix up with the "zero" value, you just specify ConvertZeroDateTime=true and detect if the result is DateTime.MinValue. You definitely shouldn't call reader.GetDateTime(), then convert the result to a string, and then back to a DateTime - you should avoid string conversions as far as you can, as they can mess things up for you pretty easily.
It's not really clear what string value you want for these "zero" values, but you should be able to special-case them with DateTime.MinValue fairly easily. Personally I'd actually try to keep the data in its "native" form as much as possible rather than converting everything to strings, but that's a different battle.

Error on int.parse

Input string was not in a correct format. At this line:
int total = 0;
total = int.Parse(TextBox2.Text) + int.Parse(TextBox4.Text) + int.Parse(TextBox6.Text) +
int.Parse(TextBox8.Text) + int.Parse(TextBox10.Text) + int.Parse(TextBox12.Text) +
int.Parse(TextBox14.Text) + int.Parse(TextBox16.Text);
Label1.Text = total.ToString();
I would like to pass the value to another page.
what does it means? T_T
Thanks in advance :)
protected void Button1_Click(object sender, EventArgs e)
{
Session["Month"] = DropDownList2.SelectedValue;
Session["expen1"] = TextBox1.Text;
Session["expen2"] = TextBox3.Text;
Session["expen3"] = TextBox5.Text;
Session["expen4"] = TextBox7.Text;
Session["expen5"] = TextBox9.Text;
Session["expen6"] = TextBox11.Text;
Session["expen7"] = TextBox13.Text;
Session["expen8"] = TextBox15.Text;
int totalvalue = 0;
totalvalue = int.Parse(TextBox2.Text) + int.Parse(TextBox4.Text) + int.Parse(TextBox6.Text) + int.Parse(TextBox8.Text) + int.Parse(TextBox10.Text) + int.Parse(TextBox12.Text) + int.Parse(TextBox14.Text) + int.Parse(TextBox16.Text);
Label1.Text = totalvalue.ToString();
Session["price1"] = TextBox2.Text;
Session["price2"] = TextBox4.Text;
Session["price3"] = TextBox6.Text;
Session["price4"] = TextBox8.Text;
Session["price5"] = TextBox10.Text;
Session["price6"] = TextBox12.Text;
Session["price7"] = TextBox14.Text;
Session["price8"] = TextBox16.Text;
Session["total"] = Label1.Text;
Server.Transfer("sum.aspx");
}
I want to store the result in sum.aspx.

If any of your TextBox values are null or are not a number, this will break. In order for this to work, all of the TextBox values will need to have a default value of 0 and you will have to restrict the input of the TextBox to numbers.

Instead of using textboxes and parsing text you trust to be numeric, use some sort of input mask or validation BEFORE parsing. Alternatively, use a different control like a Numeric up/down or numeric spinner.
You need to learn about how to handle exceptions, when to use try parse and when to use parse...

If any of the textboxes is empty, you will get an exception, since empty text cannot be parsed.
Use int.TryParse instead.

what does it means?
One of your TextBoxes contains a text which can't be parsed as an Integer.

Check Each textbox data should be numbers. if try enter string and validating with int.parse you will get this error.

It means that one of the textboxes values (TextBox#.Text) contains a value that cannot be "converted" to an integer.
What values are inside the textboxes? For example, if the textbox contains a non-numeric character it wont be able to convert, since the letter 'a' has no numeric value.

It means that one of the calls to int.Parse threw an exception because the text value was not a value that could be parsed into an Integer (e.g. the text was a non numeric value).
A better way to do this would be:
var textBoxesToParse = new [] { TextBox2, TextBox4, TextBox6, TextBox8, TextBox10, TextBox12, TextBox14, TextBox16 };
int total = 0;
foreach (var textBox in textBoxesToParse)
{
int textBoxValue;
if(int.TryParse(textBox.Text, out textBoxValue))
{
total += textBoxValue;
}
else
{
// The textbox had an invalid value, up to you what you need to do here.
}
}

As has been mentioned, the error is that one of your textboxes has either a blank or a non-numeric value.
You can use a RegularExpressionValidator so that the user is permitted to submit the form only when the values are numeric.
<asp:RegularExpressionValidator ID="RegularExpressionValidator7" runat="server"
ControlToValidate="txtLastName"Display="Dynamic" ErrorMessage="Numeric characters only"
ForeColor="Red" ValidationExpression="^[0-9]*$"
Additionally, you should also look to use tryParse or Int32.Parse(); the latter returns 0 if it is passed a null string.

Weird issue with casting substring to integer

I'm getting a weird issue with substringing. Apparently the string I get can't be cast into an Int32 for some odd reason. The error message I get when I try doing that is "input string is not in correct format". Because of this, I can't insert these values into the Database either.
Here's the code...
string width = GetMetadata(filename, 162); //returns "1280 pixels"
string height = GetMetadata(filename, 164); //returns "700 pixels"
width = width.Substring(0, width.IndexOf(' ')); //returns "1280"
height = height.Substring(0, height.IndexOf(' ')); //returns "700"
//test: "System.Convert.ToInt32(width)" will fail, giving error "input string was not in correct format"
//doing the above on "width" yields the same result
//fails, giving error "no such column: 1280" (underlying database is sqlite)
Database.NonQuery("INSERT INTO image VALUES (" + fileid + ", " + width + ", " + height + ")");

For all the normal reasons - primarily avoiding leaving data conversions to the database, and preventing SQL injection attacks - I would suggest that you perform the parsing to a number in C#, and then use a parameterized query to talk to SQLite.
In this case, that will make it a lot easier to debug - either .NET will fail to parse the string as well (in which case it's likely to be a problem with your data) or it will work, and you won't need to worry about what conversions database was performing.
EDIT: I've just seen your comment saying that Convert.ToInt32 fails as well. That's a pretty clear indication that it's the data which is causing a problem.
I'd expect your code to look something like this:
string widthText = GetMetadata(filename, 162);
string heightText = GetMetadata(filename, 164);
widthText = width.Substring(0, width.IndexOf(' ')).Trim();
heightText = height.Substring(0, height.IndexOf(' ')).Trim();
int width = int.Parse(widthText, CulutureInfo.InvariantCulture);
int height = int.Parse(widthText, CulutureInfo.InvariantCulture);
using (SQLiteCommand cmd = Database.CreateCommand())
{
cmd.CommandText = "INSERT INTO image VALUES (?, ?, ?)";
cmd.Parameters.Add(fileid);
cmd.Parameters.Add(width);
cmd.Parameters.Add(height);
cmd.ExecuteNonQuery();
}
Note that the Trim call will remove any leading spaces, which it seems was the cause of the problem.

There may be some stray whitespaces in the string variables width and height. Invoke Trim() method on the strings before casting them into integers:
width = width.Trim();
height = height.Trim();
Hope this helps. Let us know.