Csharp/C Sharp/Data Types/Number
Содержание
- 1 Converting a Number in Another Base to Base10
- 2 Converting Celsius to Fahrenheit
- 3 Converting Degrees to Radians
- 4 Converting Fahrenheit to Celsius
- 5 Converting Radians to Degrees
- 6 Declare int and use it
- 7 Determining if a String is a Valid Number by Parse functions
- 8 Faster way to get number from string
- 9 Is it a double number
- 10 Numeric Parsing Demo
- 11 shows that using an instance of the System.Int32 stucture is the same as using the int keyword
- 12 System maximums and minimums
- 13 Test for an Even or Odd Value
- 14 Use Integer.Parse to check: is it a number
- 15 Use int.Parse to check: is it an integer
- 16 Use int variable
- 17 Use regualr expression to check: is it a number
- 18 Use regualr expression to check: Is it an Unsigned Integer
- 19 Use regular expression to get number from string
Converting a Number in Another Base to Base10
<source lang="csharp"> using System; using System.Data;
class Class1{
static void Main(string[] args){
string base2 = "111";
string base8 = "117";
string base10 = "1110";
string base16 = "11F1FF";
Console.WriteLine("Convert.ToInt32(base2, 2) = " +
Convert.ToInt32(base2, 2));
Console.WriteLine("Convert.ToInt32(base8, 8) = " +
Convert.ToInt32(base8, 8));
Console.WriteLine("Convert.ToInt32(base10, 10) = " +
Convert.ToInt32(base10, 10));
Console.WriteLine("Convert.ToInt32(base16, 16) = " +
Convert.ToInt32(base16, 16));
}
}
</source>
Converting Celsius to Fahrenheit
<source lang="csharp"> using System; using System.Data; using System.Text.RegularExpressions; class Class1{
static void Main(string[] args){
Console.WriteLine(CtoF(0));
Console.WriteLine(CtoF(40));
Console.WriteLine(CtoF(50));
Console.WriteLine(CtoF(-50));
}
public static double CtoF(double celsius)
{
return (((0.9/0.5) * celsius) + 32);
}
}
</source>
Converting Degrees to Radians
<source lang="csharp"> using System; using System.Data;
class Class1{
static void Main(string[] args){
Console.WriteLine(ConvertDegreesToRadians (180));
Console.WriteLine(ConvertDegreesToRadians (90));
Console.WriteLine(ConvertDegreesToRadians (30));
}
public static double ConvertDegreesToRadians (double degrees)
{
double radians = (Math.PI / 180) * degrees;
return (radians);
}
}
</source>
Converting Fahrenheit to Celsius
<source lang="csharp"> using System; using System.Data; using System.Text.RegularExpressions; class Class1{
static void Main(string[] args){
Console.WriteLine(FtoC(0));
Console.WriteLine(FtoC(40));
Console.WriteLine(FtoC(50));
Console.WriteLine(FtoC(-50));
}
public static double FtoC(double fahrenheit)
{
return ((0.5/0.9) * (fahrenheit - 32));
}
}
</source>
Converting Radians to Degrees
<source lang="csharp"> using System; using System.Data;
class Class1{
static void Main(string[] args){
Console.WriteLine(ConvertRadiansToDegrees (2));
Console.WriteLine(ConvertRadiansToDegrees (3.1415));
Console.WriteLine(ConvertRadiansToDegrees (0));
}
public static double ConvertRadiansToDegrees(double radians)
{
double degrees = (180 / Math.PI) * radians;
return (degrees);
}
}
</source>
Declare int and use it
<source lang="csharp"> //Example3_6.cs, Page 78 using System; public class Example3_6q {
public static void Main(string[] args) {
int number1 = 12;
int number2 = 23;
Console.WriteLine("The answer is " + number1 + number2);
Console.WriteLine("The answer is " + (number1 + number2));
}
}
</source>
Determining if a String is a Valid Number by Parse functions
<source lang="csharp"> using System; using System.Data;
class Class1{
static void Main(string[] args){
string IsNotNum = "111west";
string IsNum = " +111 ";
string IsFloat = " 23.11 ";
string IsExp = " +23 e+11 ";
Console.WriteLine(int.Parse(IsNum));
Console.WriteLine(float.Parse(IsNum)); // 111
Console.WriteLine(float.Parse(IsFloat)); // 23.11
//Console.WriteLine(float.Parse(IsExp)); // throws
try
{
Console.WriteLine(int.Parse(IsNotNum));
}
catch (FormatException e)
{
Console.WriteLine("Not a numeric value: {0}", e.ToString()); // throws
}
}
}
</source>
Faster way to get number from string
<source lang="csharp"> using System; using System.Data; using System.Text.RegularExpressions; class Class1{
static void Main(string[] args){
string IsNotNum = "111west";
string IsNum = " +111 ";
string IsFloat = " 23.11 ";
string IsExp = " +23 e+11 ";
Console.WriteLine(GetNumberFromStrFaster(IsNum)); // +111
Console.WriteLine(GetNumberFromStrFaster(IsNotNum)); //
Console.WriteLine(GetNumberFromStrFaster(IsFloat)); // 23.11
Console.WriteLine(GetNumberFromStrFaster(IsExp)); //
}
public static string GetNumberFromStrFaster(string str)
{
str = str.Trim();
Match m = new Regex(@"^[\+\-]?\d*\.?[Ee]?[\+\-]?\d*$", RegexOptions.rupiled).Match(str);
return (m.Value);
}
}
</source>
Is it a double number
<source lang="csharp"> using System; using System.Data; using System.Text.RegularExpressions; class Class1{
static void Main(string[] args){
string IsNotNum = "111west";
string IsNum = " +111 ";
string IsFloat = " 23.11 ";
string IsExp = " +23 e+11 ";
Console.WriteLine(IsNumericFromTryParse(IsNum)); // True
Console.WriteLine(IsNumericFromTryParse(IsNotNum)); // False
Console.WriteLine(IsNumericFromTryParse(IsFloat)); // True
Console.WriteLine(IsNumericFromTryParse(IsExp)); // False
}
public static bool IsNumericFromTryParse(string str)
{
double result = 0;
return (double.TryParse(str, System.Globalization.NumberStyles.Float, System.Globalization.NumberFormatInfo.CurrentInfo, out result));
}
}
</source>
Numeric Parsing Demo
<source lang="csharp"> using System; public class NumericParsing {
public static void Main()
{
int value = Int32.Parse("99953");
double dval = Double.Parse("1.3433E+35");
Console.WriteLine("{0}", value);
Console.WriteLine("{0}", dval);
}
}
</source>
shows that using an instance of the System.Int32 stucture is the same as using the int keyword
<source lang="csharp"> /* C# Programming Tips & Techniques by Charles Wright, Kris Jamsa Publisher: Osborne/McGraw-Hill (December 28, 2001) ISBN: 0072193794
- /
// // TestInt.cs -- shows that using an instance of the System.Int32 stucture // is the same as using the int keyword. // // Compile this program with the following command line: // C:>csc TestInt.cs // namespace nsTestInt {
using System;
public class TestInt
{
static public void Main ()
{
System.Int32 x;
OutInt (out x);
Console.WriteLine ("The integer is " + x);
x = 42;
ShowInt (x);
ChangeInt (ref x);
Console.WriteLine ("The integer is " + x);
}
static void OutInt (out int val)
{
val = 42;
}
static void ShowInt (int val)
{
Console.WriteLine ("The value passed is " + val.ToString());
}
static void ChangeInt (ref System.Int32 val)
{
val *= 2;
}
}
}
</source>
System maximums and minimums
<source lang="csharp"> using System; class Test {
public static void Main() {
// First, print out the minimum values
Console.WriteLine("System Minimums\n");
Console.WriteLine( "MinSByte {0}", System.SByte.MinValue);
Console.WriteLine( "MinByte {0}", System.Byte.MinValue);
Console.WriteLine( "MinInt16 {0}", System.Int16.MinValue);
Console.WriteLine( "MinUInt16 {0}", System.UInt16.MinValue);
Console.WriteLine( "MinInt32 {0}", System.Int32.MinValue);
Console.WriteLine( "MinUInt32 {0}", System.UInt32.MinValue);
Console.WriteLine( "MinInt64 {0}", System.Int64.MinValue);
Console.WriteLine( "MinUInt64 {0}", System.UInt64.MinValue);
Console.WriteLine( "MinChar {0}", System.Char.MinValue);
Console.WriteLine( "MinSingle {0}", System.Single.MinValue);
Console.WriteLine( "MinDouble {0}", System.Double.MinValue);
// Console.WriteLine( "MinBoolean {0}", System.Boolean.MinValue);
Console.WriteLine( "MinDecimal {0}", System.Decimal.MinValue);
Console.WriteLine("\nSystem Maximums\n");
Console.WriteLine( "MaxSByte {0}", System.SByte.MaxValue);
Console.WriteLine( "MaxByte {0}", System.Byte.MaxValue);
Console.WriteLine( "MaxInt16 {0}", System.Int16.MaxValue);
Console.WriteLine( "MaxUInt16 {0}", System.UInt16.MaxValue);
Console.WriteLine( "MaxInt32 {0}", System.Int32.MaxValue);
Console.WriteLine( "MaxUInt32 {0}", System.UInt32.MaxValue);
Console.WriteLine( "MaxInt64 {0}", System.Int64.MaxValue);
Console.WriteLine( "MaxUInt64 {0}", System.UInt64.MaxValue);
Console.WriteLine( "MaxChar {0}", System.Char.MaxValue);
Console.WriteLine( "MaxSingle {0}", System.Single.MaxValue);
Console.WriteLine( "MaxDouble {0}", System.Double.MaxValue);
Console.WriteLine( "MaxDecimal {0}", System.Decimal.MaxValue);
}
}
</source>
Test for an Even or Odd Value
<source lang="csharp"> using System; using System.Data;
class Class1{
static void Main(string[] args){
Console.WriteLine(IsEven(0));
Console.WriteLine(IsEven(3));
Console.WriteLine(IsOdd(2));
Console.WriteLine(IsOdd(1));
}
public static bool IsEven(int intValue)
{
return ((intValue & 1) == 0);
}
public static bool IsOdd(int intValue)
{
return ((intValue & 1) == 1);
}
}
</source>
Use Integer.Parse to check: is it a number
<source lang="csharp"> using System; using System.Data; using System.Text.RegularExpressions; class Class1{
static void Main(string[] args){
string IsNotNum = "111west";
string IsNum = " +111 ";
string IsFloat = " 23.11 ";
string IsExp = " +23 e+11 ";
Console.WriteLine(IsIntegerRegEx(IsNum)); // True
Console.WriteLine(IsIntegerRegEx(IsNotNum)); // False
Console.WriteLine(IsIntegerRegEx(IsFloat)); // False
Console.WriteLine(IsIntegerRegEx(IsExp)); // False
}
public static bool IsIntegerRegEx(string str)
{
str = str.Trim();
return (Regex.IsMatch(str, @"^[\+\-]?\d+$"));
}
}
</source>
Use int.Parse to check: is it an integer
<source lang="csharp"> using System; using System.Data;
class Class1{
static void Main(string[] args){
string IsNotNum = "111west";
string IsNum = " +111 ";
string IsFloat = " 23.11 ";
string IsExp = " +23 e+11 ";
Console.WriteLine(IsNumeric(IsNum)); // True
Console.WriteLine(IsNumeric(IsNotNum)); // False
Console.WriteLine(IsNumeric(IsFloat)); // False
Console.WriteLine(IsNumeric(IsExp)); // False
Console.WriteLine();
}
public static bool IsNumeric(string str)
{
try
{
str = str.Trim();
int foo = int.Parse(str);
return (true);
}
catch (FormatException e)
{
Console.WriteLine("Not a numeric value: {0}", e.ToString());
return (false);
}
}
}
</source>
Use int variable
<source lang="csharp"> /* Mastering Visual C# .NET by Jason Price, Mike Gunderloy Publisher: Sybex; ISBN: 0782129110
- /
public class Example2_1 {
public static void Main()
{
int count = 1;
System.Console.WriteLine("count = " + count);
}
}
</source>
Use regualr expression to check: is it a number
<source lang="csharp"> using System; using System.Data; using System.Text.RegularExpressions; class Class1{
static void Main(string[] args){
string IsNotNum = "111west";
string IsNum = " +111 ";
string IsFloat = " 23.11 ";
string IsExp = " +23 e+11 ";
Console.WriteLine(IsNumericRegEx(IsNum)); // True
Console.WriteLine(IsNumericRegEx(IsNotNum)); // False
Console.WriteLine(IsNumericRegEx(IsFloat)); // True
Console.WriteLine(IsNumericRegEx(IsExp)); // False
}
public static bool IsNumericRegEx(string str)
{
str = str.Trim();
return (Regex.IsMatch(str, @"^[\+\-]?\d*\.?[Ee]?[\+\-]?\d*$"));
}
}
</source>
Use regualr expression to check: Is it an Unsigned Integer
<source lang="csharp"> using System; using System.Data; using System.Text.RegularExpressions; class Class1{
static void Main(string[] args){
string IsNotNum = "111west";
string IsNum = " +111 ";
string IsFloat = " 23.11 ";
string IsExp = " +23 e+11 ";
Console.WriteLine(IsUnsignedIntegerRegEx(IsNum)); // True
Console.WriteLine(IsUnsignedIntegerRegEx(IsNotNum)); // False
Console.WriteLine(IsUnsignedIntegerRegEx(IsFloat)); // False
Console.WriteLine(IsUnsignedIntegerRegEx(IsExp)); // False
}
public static bool IsUnsignedIntegerRegEx(string str)
{
str = str.Trim();
return (Regex.IsMatch(str, @"^\+?\d+$"));
}
}
</source>
Use regular expression to get number from string
<source lang="csharp"> using System; using System.Data; using System.Text.RegularExpressions; class Class1{
static void Main(string[] args){
string IsNotNum = "111west";
string IsNum = " +111 ";
string IsFloat = " 23.11 ";
string IsExp = " +23 e+11 ";
Console.WriteLine(GetNumberFromStr(IsNum)); // +111
Console.WriteLine(GetNumberFromStr(IsNotNum)); //
Console.WriteLine(GetNumberFromStr(IsFloat)); // 23.11
Console.WriteLine(GetNumberFromStr(IsExp)); //
}
public static string GetNumberFromStr(string str)
{
str = str.Trim();
Match m = Regex.Match(str, @"^[\+\-]?\d*\.?[Ee]?[\+\-]?\d*$");
return (m.Value);
}
}
</source>
