public void WriteFile(ContractCollection contractColl)
{
/*A good practice is to use these objects in a using statement so that the unmanaged resources are correctly disposed. The using statement automatically calls Dispose on the object when the code that is using it has completed
*/
//source: https://docs.microsoft.com/en-us/dotnet/api/system.io.streamwriter?view=netframework-4.8
string fileName = "contract.txt";
using (StreamWriter fileWriter = File.CreateText(fileName))
{
foreach (Contract aContract in contractColl.AllContracts)
{
//each othe commas here delimit the file to seperate the information
//when the file is read we can use .split method in reading to seperate
//each word into an index
fileWriter.Write(aContract.number);
fileWriter.Write(",");
fileWriter.Write(aContract.name);
fileWriter.Write(",");
fileWriter.Write(aContract.amount);
fileWriter.Write(",");
fileWriter.WriteLine(aContract.startDate.ToShortDateString());
}
}
}
public void ReadFile(ContractCollection contractColl)
{
//the using example was used in the writer, but the same thing can applied here,
//but for all purposes of showing what the other way looks like I will leave this example
//more open to the intended way the professor wants the code written.
//Here the reader variable is created, a delimiter is set up, and
//string line will hold each line read in the file.
StreamReader infile;
string file = "contract.txt";
char delimiter = ',';
string line;
string[] fields = new string[4];
//File existance is checked with File.Exists
if (File.Exists(file))
{
//here if the file exists, the file is opened and read it until
//the end of the file stream is reached
infile = File.OpenText(file);
while (!infile.EndOfStream)
{
//Step one: Put a file line in the string line
//Step Two: split words into an array of words(in this case fields)
//and instantiate the contract object
//Step Three: Insert strings into appropriate places
//of the contract object and add the contract to the contract
//collection
line = infile.ReadLine();
fields = line.Split(delimiter);
Contract aContract = new Contract();
aContract.number = fields[0];
aContract.name = fields[1];
aContract.amount = double.Parse(fields[2]);
aContract.startDate = DateTime.Parse(fields[3]);
contractColl.AddContract(aContract);
}
infile.Close();
}
}
