我想在一个包含人口普查数据的文件中阅读。根据这些数据，我需要输出在特定地区居住的人数以及特定年龄段的人数。
问题是我的输出显示全部为零，除了＆＃34;年龄在18岁以下＆＃34;显示100的行。作为参考，正在读入的文件有100个人和22个区。
这是我的代码：
class Program
{
static void Main(string[] args)
{
FileStream fStream = new FileStream("censusdata.txt", FileMode.Open, FileAccess.Read);
StreamReader inFile = new StreamReader(fStream);
string input = "";
int age = 0;
int district = 0;
const int AGE = 5;
const int DISTRICT = 22;
string[] fields;
bool ageBool = true;
bool distBool = true;
int[] ageCount = new int[AGE];
int[] ageRange = new int[AGE] { 0, 18, 30, 45, 64 };
int[] districtCount = new int[DISTRICT];
int[] districtRange = new int[DISTRICT];
input = inFile.ReadLine();
while(input != null)
{
fields = input.Split(',');
input = inFile.ReadLine();
if (ageBool)
{
validDataAge(fields, input, age, ageBool);
getValuePerAge(age, ageCount, ageRange);
}
else
Console.WriteLine("error");
if (distBool)
{
validDataDistrict(fields, input, district, distBool);
getValuePerDistrict(district, districtCount, districtRange);
}
else
Console.WriteLine("error");
}
displayOutput(districtCount, ageCount);
}
static bool validDataAge(string[] fieldsArray, string inputData, int a, bool age)
{
if (int.TryParse(fieldsArray[0], out a))
{
age = true;
return age;
}
else
{
age = false;
return age;
}
}
static bool validDataDistrict(string[] fieldsArray, string inputData, int d, bool district)
{
if (int.TryParse(fieldsArray[3], out d))
{
district = true;
return district;
}
else
{
district = false;
return district;
}
}
static void getValuePerDistrict(int d, int[] districtCountArray, int[] districtRangeArray)
{
for (int x = 1; x <= districtRangeArray.Length; x++)
{
if (x == d)
districtCountArray[x]++;
}
}
static void getValuePerAge(int a, int[] ageCountArray, int[] ageRangeArray)
{
int index = ageRangeArray.Length - 1;
while(a < ageRangeArray[index])
index--;
ageCountArray[index]++;
}
public static void displayOutput(int[] districtCountArray, int[] ageCountArray)
{
for (int x = 0; x < districtCountArray.Length; x++)
{
Console.WriteLine("District " + (x + 1) + ": Population = " + districtCountArray[x]);
}
Console.WriteLine("");
Console.WriteLine("");
Console.WriteLine("");
Console.WriteLine("");
Console.WriteLine("Age Under 18: Population = " + ageCountArray[0]);
Console.WriteLine("Ages 18-30: Population = " + ageCountArray[1]);
Console.WriteLine("Ages 31-45: Population = " + ageCountArray[2]);
Console.WriteLine("Ages 46-64: Population = " + ageCountArray[3]);
Console.WriteLine("65 & Over: Population = " + ageCountArray[4]);
}
}
这是输出：
District 1: Population = 0 District 2: Population = 0 District 3: Population = 0 District 4: Population = 0 District 5: Population = 0 District 6: Population = 0 District 7: Population = 0 District 8: Population = 0 District 9: Population = 0 District 10: Population = 0 District 11: Population = 0 District 12: Population = 0 District 13: Population = 0 District 14: Population = 0 District 15: Population = 0 District 16: Population = 0 District 17: Population = 0 District 18: Population = 0 District 19: Population = 0 District 20: Population = 0 District 21: Population = 0 District 22: Population = 0 Age Under 18: Population = 100 Ages 18-30: Population = 0 Ages 31-45: Population = 0 Ages 46-64: Population = 0 65 & Over: Population = 0 Press any key to continue . . .
答案 0 :(得分：0)
您的int a方法需要out int a为validDataAge：
static bool validDataAge(string[] fieldsArray, string inputData, out int a, bool age)
{
if (int.TryParse(fieldsArray[0], out a))
{
age = true;
return age;
}
else
{
age = false;
return age;
}
}
但是，正如进一步的建议，该方法可以写成：
static bool validDataAge(string inputData, out int a)
{
return int.TryParse(inputData, out a);
}
但是，validDataAge基本上与int.TryParse功能相同，因此您可以完全删除validDataAge。
答案 1 :(得分：0)
你所表现出的承诺;这是一个很好的学生初学者的努力。我不知道你会理解多少这些，但我希望你至少有机会看到更接近它的外观，以帮助你养成良好的习惯。
public class CensusRecord
{
public int Age {get;set;}
public int DistrictID {get;set;}
public bool DataReady {get;private set;}
public static CensusRecord FromDataLine(string line)
{
// I don't normally recommend .Split() for CSV data -- too many edge cases
// -- but this didn't seem like the time to pull in a CSV reader
var fields = line.Split(',');
int age = 0, district = 0;
var result = new CensusRecord();
result.DataReady = true;
if (int.TryParse(fieldsArray[0], out age))
result.Age = age;
else
result.DataReady = false;
if (int.TryParse(fieldsArray[3], out district))
result.DistrictID = district;
else
result.DataReady = false;
return result;
}
}
class Program
{
static IEnumerable<CensusRecord> LoadData(string filename)
{
return File.ReadLines(filename)
.Select(line => CensusRecord.FromDataLine(line))
.Where(r => r.DataReady);
}
static void Main(string[] args)
{
var data = LoadData("censusdata.txt").ToList();
DisplayDistrictPopulations(data);
Console.WriteLine("");
DisplayAgeGroups(data);
Console.WriteLine("Press any key to continue...");
Console.ReadKey(true);
}
static void DisplayDistrictPopulations(IEnumerable<CensusRecord> data)
{
foreach(var district in data.GroupBy(r => r.DistrictID).OrderBy(g => g.Key))
{
Console.WriteLine("District {0}: Population = {1}", district.Key, district.Count());
}
}
static void DisplayAgeGroups(IEnumerable<CensusRecord> data)
{
var groups = data.GroupBy(r => {
if (r.Age < 18) return 0;
if (r.Age <= 30) return 1;
if (r.Age <= 45) return 2;
if (r.Age <= 64) return 3;
return 4;
}).OrderBy(g => g.Key);
string[] ageStrings = {"Age Under 18", "Ages 18-30","Ages 31-45", "Ages 46-64", "65 & Over"};
foreach (var age in groups)
{
Console.WriteLine("{0}: Population = {1}", ageStrings[age.Key], age.Count());
}
}
}