How would you get a variable from each object in a list?
I've got this so far:
void SortList()
{
int j = modules.Count;
string[] titles = new string[j];
for (int i = 0; i > modules.Count; i++)
{
titles[i] =
}
}
And I'm trying to get the variable "code" from each object in modules.
thanks.
Implying modules is a list or an array,
void SortList()
{
int j = modules.Count;
string[] titles = new string[j];
foreach (String title in modules)
{
titles[i] = title.code
}
}
As stated by Cuong Le, you could also use Linq to get a shorter version (Depending of which .Net version you are on).
titles = modules.Select(x => x.code).ToArray();
You can use LINQ with simple code with Select method:
titles = modules.Select(x => x.code).ToArray();
Related
class Program
{
public static bool Like(string toSearch,string toFind)
{
if (toSearch.Contains(toFind))
return true;
else
return false;
}
static void Main(string[] args)
{
List<string> str = new List<string>();
List<string> strNew = new List<string>();
str.Add("abdecacd");
str.Add("facdgh");
str.Add("iabcacdjk");
str.Add("lmn");
str.Add("opqe");
str.Add("acbd");
str.Add("efgh");
string strToSearch= "acd,abc,abcacd,al";
string[] desc = strToSearch.Split(',');
for(int i = 0; i < str.Count; i++)
{
for(int j = 0; j < desc.Length; j++)
{
if(Like(str[i].ToString(),desc[j].ToString()))
{
strNew.Add(str[i].ToString());
break;
}
}
}
if(strNew != null)
{
foreach(string strPrint in strNew)
{
Console.WriteLine(strPrint);
}
}
}
}
How to write a linq query for above code,in this strToSearch variable value will be dynamic,user will enter comma separated values,user may enter as many comma separated values as user wants,I want to write a linq query which will find all the values in List which will contain the value entered by user.
Reason I need linq query,because linq is used in my application. Kindly help me out on this.
The LINQ expression is:
List<string> strNew = str.Where(x => desc.Any(y => x.Contains(y))).ToList();
that can even be simplified (simplified for the .NET runtime, not for the programmer) to:
List<string> strNew = str.Where(x => desc.Any(x.Contains)).ToList();
by removing an intermediate lambda function.
In general there is no "speed" difference between what you wrote and what I wrote. Both expressions are O(m*n), with m = str.Length and n = desc.Length, so O(x^2). You aren't doing an exact search, so you can't use the usual trick of creating an HashSet<string> (or doing str.Intersect(desc).ToList() that internally does the same thing).
Variable.cs
public string[] CcEmails { get; set; }
Mail.cs
EDTO.CcEmails = dr["rsh_ccmail"].ToString().Split(';');
here i got two strings eg. xxxx#gmail.com ; yyy#gmail.com
MailProcess.cs
dataRPT1=get data from sql
EDTO.CcEmails = new string[dataRPT1.Rows.Count];
for (int i = 0; i < dataRPT1.Rows.Count; i++)
{
EDTO.CcEmails[i] = dataRPT1.Rows[i]["email_addr"].ToString();
}
Here i got list of string eg.aaa#gmail.com ......
I am try to add with existing but it add only new values..Anyone could help me..
I tend to use union, although that will remove duplicate entries. But to keep all entries you can use Concat on the array.
var emailString = "me#test.com;you#test.com";
string[] emails = emailString.Split(';');
string[] emailsFromSQL = new string[3];
emailsFromSQL[0] = "everyone#test.com";
emailsFromSQL[1] = "everyone2#test.com";
emailsFromSQL[2] = "everyone2#test.com";
//No Duplicates
var combined = emails.Union(emailsFromSQL).ToArray();
//Duplicates
var allCombined = emails.Concat(emailsFromSQL).ToArray();
Thanks
I find the easiest way of doing this is to create a list, add items to the list, then use string.Join to create the new string.
var items = new List<string>();
for (int i = 0; i < dataRPT1.Rows.Count; i++)
{
items.Add(dataRPT1.Rows[i]["email_addr"].ToString());
}
EDTO.CcEmails = string.Join(";", items);
Update after changed question:
If the type of the CcEmails is an array, the last line could be:
EDTO.CcEmails = items.ToArray();
I have a implememtation where i need to loop through a collection of documents and based on certain condition merge the documents .
The merge condition is very simple, if present document's doctype is same as later document's doctype, then copy all the pages from the later doctype and append it to the pages of present document's and remove the later document from the collection.
Note : Both response.documents and response.documents[].pages are List<> collections.
I was trying this but was getting following exception Once I remove the document.
collection was modified enumeration may not execute
Here is the code:
int docindex = 0;
foreach( var document in response.documents)
{
string presentDoctype = string.Empty;
string laterDoctype = string.Empty;
presentDoctype = response.documents[docindex].doctype;
laterDoctype = response.documents[docindex + 1].doctype;
if (laterDoctype == presentDoctype)
{
response.documents[docindex].pages.AddRange(response.documents[docindex + 1].pages);
response.documents.RemoveAt(docindex + 1);
}
docindex = docindex + 1;
}
Ex:
reponse.documents[0].doctype = "BankStatement" //page count = 1
reponse.documents[1].doctype = "BankStatement" //page count = 2
reponse.documents[2].doctype = "BankStatement" //page count = 2
reponse.documents[3].doctype = "BankStatement" //page count = 1
reponse.documents[4].doctype = "BankStatement" //page count = 4
Expected result:
response.documents[0].doctype = "BankStatement" //page count = 10
Please suggest.Appreciate your help.
I would recommend you to look at LINQ GroupBy and Distinct to process your response.documents
Example (as I cannot use your class, I give example using my own defined class):
Suppose you have DummyClass
public class DummyClass {
public int DummyInt;
public string DummyString;
public double DummyDouble;
public DummyClass() {
}
public DummyClass(int dummyInt, string dummyString, double dummyDouble) {
DummyInt = dummyInt;
DummyString = dummyString;
DummyDouble = dummyDouble;
}
}
Then doing GroupBy as shown,
DummyClass dc1 = new DummyClass(1, "This dummy", 2.0);
DummyClass dc2 = new DummyClass(2, "That dummy", 2.0);
DummyClass dc3 = new DummyClass(1, "These dummies", 2.0);
DummyClass dc4 = new DummyClass(2, "Those dummies", 2.0);
DummyClass dc5 = new DummyClass(3, "The dummies", 2.0);
List<DummyClass> dummyList = new List<DummyClass>() { dc1, dc2, dc3, dc4, dc5 };
var groupedDummy = dummyList.GroupBy(x => x.DummyInt).ToList();
Will create three groups, marked by DummyInt
Then to process the group you could do
for (int i = 0; i < groupedDummy.Count; ++i){
foreach (DummyClass dummy in groupedDummy[i]) { //this will process the (i-1)-th group
//do something on this group
//groupedDummy[0] will consists of "this" and "these", [1] "that" and "those", while [2] "the"
//Try it out!
}
}
In your case, you should create group based on doctype.
Once you create groups based on your doctype, everything else would be pretty "natural" for you to continue.
Another LINQ method which you might be interested in would be Distinct. But I think for this case, GroupBy would be the primary method you would like to use.
Use only "for loop" instead of "foreach".
foreach will hold the collection and cannot be modified while looping thru it.
Here is an example using groupBy, hope this help.
//mock a collection
ICollection<string> collection1 = new List<string>();
for (int i = 0; i < 10; i++)
{
collection1.Add("BankStatement");
}
for (int i = 0; i < 5; i++)
{
collection1.Add("BankStatement2");
}
for (int i = 0; i < 4; i++)
{
collection1.Add("BankStatement3");
}
//merge and get count
var result = collection1.GroupBy(c => c).Select(c => new { name = c.First(), count = c.Count().ToString() }).ToList();
foreach (var item in result)
{
Console.WriteLine(item.name + ": " + item.count);
}
Just use AddRange()
response.documents[0].pages.AddRange(response.documents[1].pages);
it will merge all pages of document[1] with the document[0] into document[0]
I'm building an android application where I need to create a simple list of String items, which i will then add a specific control for each item in the list.
This is the list I want to create:
List<String> projects = new List<String>(); // How?
The code I was trying:
String projects = new string[] { "hey","yo","app","xamarin","c","xaml" };
I need to count the items, something like this:
int amount = projects.Count(); // Can I do this?
Then adding the controls for each item in the list
// Add the tiles, one by one
for (int i = 0; i < amount; i++)
{
// Inflate the tile
var tile = LayoutInflater.Inflate (Resource.Layout.Tile, null);
// Set its attributes
tile.FindViewById<TextView> (Resource.Id.projectName).Text = currentProject;
// Add the tile
projectScrollView.AddView (tile);
}
"currentProject" string is retrieved from SharedPreferences, just haven't got that far yet
var projects = new List<String>() { "hey","yo","app","xamarin","c","xaml" };
if you are using the array to store what values you want in your list use the foreach
List<string>project = new List<string>();
string[] projects = { "hey","yo","app","xamarin","c","xaml" };
foreach(string str in projects)
{
project.Add(str);
}
for (int i = 0; i < projects.Length; i++)
{
// Inflate the tile
var tile = LayoutInflater.Inflate (Resource.Layout.Tile, null);
// Set its attributes
tile.FindViewById<TextView> (Resource.Id.projectName).Text = currentProject;
// Add the tile
projectScrollView.AddView (tile);
}
// you can get items from your list by using project.Count, your List<string> instead of projects.Length your array and take information from your list and output your tiles that way
To initialize a List<string> with collection initializer use the below syntax.
List<String> projects = new List<String>(){"hey","yo","app","xamarin","c","xaml"};
Count is not a method it is a property. You need property syntax.
int amount = projects.Count;
int amount = projects.Length;
that is how you can set the value of the int. It doesnt appear that you are populating your list with that code.
I have a .csv with the following headers and an example line from the file.
AgentID,Profile,Avatar,In_Time,Out_Time,In_Location,Out_Location,Target_Speed(m/s),Distance_Traveled(m),Congested_Duration(s),Total_Duration(s),LOS_A_Duration(s),LOS_B_Duration(s),LOS_C_Duration(s),LOS_D_Duration(s),LOS_E_Duration(s),LOS_F_Duration(s)
2177,DefaultProfile,DarkGreen_LowPoly,08:00:00,08:00:53,East12SubwayportalActor,EWConcourseportalActor,1.39653,60.2243,5.4,52.8,26.4,23,3.4,0,0,0
I need to sort this .csv by the 4th column (In_time) by increasing time ( 08:00:00, 08:00:01) and the 6th (In_Location) by alphabetical direction (e.g. East, North, etc).
So far my code looks like this:
List<string> list = new List<string>();
using (StreamReader reader = new StreamReader("JourneyTimes.csv"))
{
string line;
while ((line = reader.ReadLine()) != null)
{
line.Split(',');
list.Add(line);
}
I read in the .csv and split it using a comma (there are no other commas so this is not a concern). I then add each line to a list. My issue is how do I sort the list on two parameters and by the headers of the .csv.
I have been looking all day at this, I am relatively new to programming, this is my first program so I apologize for my lack of knowledge.
You can use LINQ OrderBy/ThenBy:
e.g.
listOfObjects.OrderBy (c => c.LastName).ThenBy (c => c.FirstName)
But first off, you should map your CSV line to some object.
To map CSV line to object you can predefine some type or create it dynamically
from line in File.ReadLines(fileName).Skip(1) //header
let columns = line.Split(',') //really basic CSV parsing, consider removing empty entries and supporting quotes
select new
{
AgentID = columns[0],
Profile = int.Parse(columns[1]),
Avatar = float.Parse(columns[2])
//other properties
}
And be aware that like many other LINQ methods, these two use deferred execution
You are dealing with two distinct problems.
First, ordering two columns in C# can be achieved with OrderBy, ThenBy
public class SpreadsheetExample
{
public DateTime InTime { get; set; }
public string InLocation { get; set; }
public SpreadsheetExample(DateTime inTime, string inLocation)
{
InTime = inTime;
InLocation = inLocation;
}
public static List<SpreadsheetExample> LoadMockData()
{
int maxMock = 10;
Random random = new Random();
var result = new List<SpreadsheetExample>();
for (int mockCount = 0; mockCount < maxMock; mockCount++)
{
var genNumber = random.Next(1, maxMock);
var genDate = DateTime.Now.AddDays(genNumber);
result.Add(new SpreadsheetExample(genDate, "Location" + mockCount));
}
return result;
}
}
internal class Class1
{
private static void Main()
{
var mockData = SpreadsheetExample.LoadMockData();
var orderedResult = mockData.OrderBy(m => m.InTime).ThenBy(m => m.InLocation);//Order, ThenBy can be used to perform ordering of two columns
foreach (var item in orderedResult)
{
Console.WriteLine("{0} : {1}", item.InTime, item.InLocation);
}
}
}
Now you can tackle the second issue of moving data into a class from Excel. VSTO is what you are looking for. There are lots of examples online. Follow the example I posted above. Replace your custom class in place of SpreadSheetExample.
You may use a DataTable:
var lines = File.ReadAllLines("test.csv");
DataTable dt = new DataTable();
var columNames = lines[0].Split(new char[] { ',' });
for (int i = 0; i < columNames.Length; i++)
{
dt.Columns.Add(columNames[i]);
}
for (int i = 1; i < lines.Length; i++)
{
dt.Rows.Add(lines[i].Split(new char[] { ',' }));
}
var rows = dt.Rows.Cast<DataRow>();
var result = rows.OrderBy(i => i["In_time"])
.ThenBy(i => i["In_Location"]);
// sum
var sum = rows.Sum(i => Int32.Parse(i["AgentID"].ToString()));