Develop Reference

How to compare dynamically in .NET Core

This is the conditional rule configured in the database. The rules configured for each user are as follows。
| key | expression |rule|
|:---- |:--------------:|---:|
| 001 | >=500 and <=600| 1.2|
| 001 | >600 | 2.0|
| 002 | ==400 | 4.0|
| 002 | !=700 | 5.0|
| 003 | ==100 || ==200 | 0.5|
I need to get the conditional dynamic judgment that the key is 001
Below is my current code, I want generated C# code like this
if (item.TotalDaySam >= 500 && item.TotalDaySam <= 600)
{
// return Amount * 001 rule(1.2)
}
else if (item.TotalDaySam > 600)
{
// return Amount * 001 rule(2.0)
}
else
{
// retrun Amount
}
How do I get the configuration of the database to dynamically generate the judgment code to perform different logical calculations. I found a similar project RulesEngine, but I don't know how to implement it.

If you can store your data like this :
x>=500 && x<=600
x>600
x==600
x!=600
And then iterate foreach line replacing each time x by "item.TotalDaySam".
Finally you can find help from this post to parse the string into a if statement : C# Convert string to if condition
(sorry for the answer instead of comment I am not expert enough to have the right to comment ^^)

Trim string in c# output last string

I'm currently making a Game and I have already split the string everything right but how I can trim the string and output the last line or a line in the middle?
Code:
text = "Username:King100 ID:100 Level:10";
string[] splittext = text.Split(' ');
foreach (var texs in splittext)
{
Console.WriteLine(texs);
}
Output:
Username:King100
ID:100
Level:10
I just want display the level 10 in the Console how thats works?
thanxs for helping.
Edit: the level can be changed often like 10 or 100 or 1000

Regex is more flexible solution. But if your text format is contsant, you can use this simple way:
string level = text.Substring(text.LastIndexOf(':') + 1);

You can also use a Regular Expression to solve this:
var regex = new Regex(#"Level:(?<Level>\d*)");
var matches = regex.Matches("Username:King100 ID:100 Level:10");
if (matches.Count > 0 && matches[0].Success)
{
Console.WriteLine(matches[0].Groups["Level"].Value);
}

var text = "Username:King100 ID:100 Level:10";
/*
Splits the given string on spaces and then splits on ":"
and creates a Dictionary ("Dictionary<TKey, TValue>")
*/
var dict = text.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries)
.Select(part => part.Split(':'))
.ToDictionary(split => split[0], split => split[1]);
//If the dictionary count is greater than Zero
if(dict.Count > 0)
{
var levelValue = dict["Level"].ToString();
}

OK, because i'm annoying and totally bored of work, i decided to benchmark everyone's solutions.
The premise was simply to make an array of 1000 (scale) lines of strings (in the given format) with random positive int on the end;
Note : I made every solution int.Parse the result, as it seemed more useful
Mine
This just uses fixed, unsafe, pointers and no error checking
var level = 0;
fixed (char* pitem = item)
{
var len = pitem + item.Length;
for (var p = pitem ; p < len; p++)
if (*p >= '0' && *p <= '9')
level = level * 10 + *p - 48;
else
level = 0;
}
Results
Mode : Release
Test Framework : .NET Framework 4.7.1
Benchmarks runs : 1000 times (averaged)
Scale : 1,000
Name | Average | Fastest | StDv | Cycles | Pass | Gain
--------------------------------------------------------------------------
Mine | 0.095 ms | 0.085 ms | 0.01 | 317,205 | Yes | 96.59 %
Sanan | 0.202 ms | 0.184 ms | 0.02 | 680,747 | Yes | 92.75 %
Zaza | 0.373 ms | 0.316 ms | 0.10 | 1,254,302 | Yes | 86.60 %
Kishore | 0.479 ms | 0.423 ms | 0.06 | 1,620,756 | Yes | 82.81 %
Hussein | 1.045 ms | 0.946 ms | 0.11 | 3,547,305 | Yes | 62.50 %
Maccettura | 2.787 ms | 2.476 ms | 0.39 | 9,474,133 | Base | 0.00 %
Hardkoded | 6.691 ms | 5.927 ms | 0.67 | 22,750,311 | Yes | -140.09 %
Tom | 11.561 ms | 10.635 ms | 0.78 | 39,344,419 | Yes | -314.80 %
Summary
All the solutions do different things in different ways, comparing them is not really apples to apples.
Don't use mine, its totally unrealistic and only for fun. Use the version that makes the most sense to you, that is the most robust and easiest to maintain.
As always, regex is the slowest.

If level is always the last part of the string, and all you care about is the actual number, then you can just do:
var level = text.Split(':').LastOrDefault();
This would just split on ':' and give you the last (or default) element. Given your example input, level = "10".

Try this:
string input = "Username:King100 ID:100 Level:10";
Match m = Regex.Match(input, #"\s*Level:(?<level>\d+)");
if (m.Success&& m.Groups["level"].Success)
Console.WriteLine(m.Groups["level"].Value);
Also works for:
string input = "Username:King100 Level:10 ID:100";

string text = texs.Substring(texs.IndexOf("Level:")+6);
System.Console.WriteLine(text);

How can I report on the name of an object with fluent assertions

I have a test that checks several objects in a table on our website. The test is written in SpecFlow and C#
It looks something like this:
When I click proceed
Then I should see the following values
| key | value |
| tax | 5.00 |
| delivery | 5.00 |
| subtotal | 20.00 |
My code behind for the "Then" step is something similar to:
[StepDefinition("I should see the following values")]
public void IShouldSeeTheFollowingValues(Table table)
{
var basketSummary = new BasketModel();
foreach (var row in table.Rows)
{
switch (row["key"])
{
case "tax":
basketSummary.Tax.Should().Be(row["value"]);
break;
case "delivery":
basketSummary.Delivery.Should().Be(row["value"]);
break;
case "subtotal":
basketSummary.Subtotal.Should().Be(row["value"]);
break;
}
}
}
The problem with this is in our build logs if the test errors it looks something like this:
When I click proceed
-> done: OrderConfirmationPageSteps.ClickProceed() (1.0s)
Then I should see the following values
--- table step argument ---
| key | value |
| tax | 5.00 |
| delivery | 5.00 |
| subtotal | 20.00 |
-> error: Expected value to be 5.00, but found 1.00.
as you can see above its hard to distinguish which object it means... when it says it expects it to be 5.00
Is there a way I can modify the output to say something along the lines of:
-> error: Expected value of Tax to be 5.00, but found 1.00.

You can do two things:
Pass a reason phrase to the Be() method, e.g.
`basketSummary.Delivery.Should().Be(row["value"], "because that's
the tax value");
Wrap the call in an AssertionScope and pass the description (the context) into its constructor, like
this

In the latest version https://fluentassertions.com/introduction#subject-identification
string username = "dennis";
username.Should().Be("jonas");
//will throw a test framework-specific exception with the following message:
Expected username to be "jonas" with a length of 5,
but "dennis" has a length of 6, differs near "den" (index 0).
Fluent Assertions can use the C# code of the unit test to extract the
name of the subject and use that in the assertion failure.
Since it needs the debug symbols for that, this will require you to
compile the unit tests in debug mode, even on your build servers.

Regex Pattern for filter out anything that doesn't Match

Using Regex.Replace(mystring, #"[^MV:0-9]", "") will remove any Letters that are not M,V,:, or 0-9 (\d could also be used) the problem is I want to remove anything that is not MV: then numbers.
I need to replace anything that is not this pattern with nothing:
Starting String | Wanted Result
---------------------------------------------------------
sdhfuiosdhusdhMV:1234567890sdfahuosdho | MV:1234567890
MV:2138911230989hdsafh89ash32893h8u098 | MV:2138911230989
809308ej0efj0934jf0934jf4fj84j8904jf09 | Null
123MV:1234321234mnnnio234324234njiojh3 | MV:1234321234
mdfmsdfuiovvvajio123oij213432ofjoi32mm | Null
But what I get with what I have is:
Starting String | Returned Result
---------------------------------------------------------
sdhfuiosdhusdhMV:1234567890sdfahuosdho | MV:1234567890
MV:2138911230989hdsafh89ash32893h8u098 | MV:213891123098989328938098
809308ej0efj0934jf0934jf4fj84j8904jf09 | 809308009340934484890409
123MV:1234321234mnnnio234324234njiojh3 | 123MV:12343212342343242343
mdfmsdfuiovvvajio123oij213432ofjoi32mm | mmvvv1232134232mm
And even if there is a Regex pattern for this would I be better off using something along the lines of:
if (Regex.IsMatch(strMyString, #"MV:"))
{
string[] strarMyString = Regex.Split(strMyString, #"MV:");
string[] strarNumbersAfterMV = Regex.Split(strarMyString[1], #"[^\d]");
string WhatIWant = strarNumbersAfterMV[0]
}
If I went with the Latter option would there be away to have:
string[] strarNumbersAfterMV = Regex.Split(strarMyString[1], #"[^\d]");
Only make one split at the first change from numbers? (It will always start with number following the MV:)

Can't you just do:
string matchedText = null;
var match = Regex.Match(myString, #"MV:[0-9]+");
if (match.Success)
{
matchedText = Value;
}
Console.WriteLine((matchedText == null) ? "Not found" : matchedText);
That should give you exactly what you need.

FIX Reading Repeating groups

I have a FIX log file. I'm iterating on the lines, putting each string into
Message m = new Message(str, false)
Because for some reason, validation fails on the file (even the first line). Now, I see that it's a 35=X type, and 268=4 (i.e. NoMDEntries=4, so I should have 4 groups in the message)
BUT, in the debug display I am not seeing any groups. m.base._groups has a count of 0.
The string in question is:
1128=9 | 9=363 | 35=X | 49=CME | 34=3151 | 52=20121216223556363 | 75=20121217 | 268=4 | 279=0 | 22=8 | 48=43585 | 83=902 | 107=6EH3 | 269=4 | 270=13186 | 273=223556000 | 286=5 | 279=0 | 22=8 | 48=43585 | 83=903 | 107=6EH3 | 269=E | 270=13186 | 271=9 | 273=223556000 | 279=0 | 22=8 | 48=43585 | 83=904 | 107=6EH3 | 269=F | 270=13185 | 273=223556000 | 279=1 | 22=8 | 48=43585 | 83=905 | 107=6EH3 | 269=0 | 270=13186 | 271=122 | 273=223556000 | 336=0 | 346=10 | 1023=1 | 10=179 |
Another thing is how do I read the groups? Instinctively, I want to do something like
for (int i = 1; i <= noMDEntries; i++) {
Group g = m.GetGroup(i);
int action = Int32.Parse(g.GetField(279));
....
}
But that's not how it works and I haven't found documentation with better explanations.
Thanks for the help,
Yonatan.

From your code snippets, I think you're using QuickFIX/n, the native C# implementation, so I will answer accordingly.
1) Your message construction is failing because you didn't provide a DataDictionary.
Use Message::FromString instead:
Message m = new Message();
m.FromString(msg_str, false, data_dic, data_dic, someMsgFactory);
Even better, use MarketDataIncrementalRefresh::FromString to get the right return type.
You can see some uses of this function here:
https://github.com/connamara/quickfixn/blob/master/UnitTests/MessageTests.cs
2) To read groups... well, QF/n has a doc page on that, which I think explains it pretty well.
http://quickfixn.org/tutorial/repeating-groups