C# Number Examples

• Numbers in C#
• Check number
• Display numbers
• Display numbers to 2 decimal places
• Display numbers with thousands separators
• Convert String to Number
• Create random number

C# Basic

• Application in C#
• Config in C#
• Error in C#
• Environment variables in C#

C# Data Type

• Byte in C#
• Number in C#
• String in C#
• List in C#
• Array in C#
• Dictionary in C#
• Enum in C#
• Structure in C#
• DateTime in C#

C# OOP

• Object in C#
• Method in C#

C# IO

• File in C#
• CSV in C#
• JSON in C#
• XML in C#

C# Graphics & UI

• Image in C#
• Color in C#
• Controls in C#

C# Advanced

• Clipboard in C#
• Excel Column in C#
• foreach in C#
• DataTable in C#
• Email in C#
• Guid in C#
• HTTP in C#
• LINQ in C#
• Stream in C#

Convert String to Number in C#

In C#, you can parse a string with a decimal point to a double using the Double.Parse method, and you can parse a string with a decimal point to an integer using the Int32.Parse method. You can also convert a string to an integer using the Int32.Parse method, convert a hexadecimal string to an integer using the Convert.ToInt32 method, convert a List<string> to a List<int> using the List.ConvertAll method, and convert a string[] to an int[] using the Array.ConvertAll method. Here are some examples:

Parsing a String with a Decimal Point to a Double

string number = "123.456";
double parsedNumber = Double.Parse(number);

In this example, the number variable contains a string value. The Double.Parse method is called with the number variable as the argument to parse the string to a double. The resulting double value is stored in the parsedNumber variable.

Parsing a String with a Decimal Point to an Integer

string number = "123";
int parsedNumber = Int32.Parse(number);

In this example, the number variable contains a string value. The Int32.Parse method is called with the number variable as the argument to parse the string to an integer. The resulting integer value is stored in the parsedNumber variable.

Converting a String to an Integer

string number = "123";
int convertedNumber = Int32.Parse(number);

In this example, the number variable contains a string value. The Int32.Parse method is called with the number variable as the argument to convert the string to an integer. The resulting integer value is stored in the convertedNumber variable.

Converting a Hexadecimal String to an Integer

string hexadecimalNumber = "7B";
int convertedNumber = Convert.ToInt32(hexadecimalNumber, 16);

In this example, the hexadecimalNumber variable contains a hexadecimal string value. The Convert.ToInt32 method is called with the hexadecimalNumber variable as the first argument and 16 as the second argument to convert the hexadecimal string to an integer. The resulting integer value is stored in the convertedNumber variable.

Converting a List<string> to a List<int>

List<string> stringList = new List<string>() { "123", "456", "789" };
List<int> intList = stringList.ConvertAll(s => Int32.Parse(s));

In this example, the stringList variable contains a list of string values. The ConvertAll method is called on the stringList variable with a lambda expression that calls the Int32.Parse method on each string value to convert them to integer values. The resulting List<int> is stored in the intList variable.

Converting a string[] to an int[]

string[] stringArray = new string[] { "123", "456", "789" };
int[] intArray = Array.ConvertAll(stringArray, s => Int32.Parse(s));

In this example, the stringArray variable contains an array of string values. The Array.ConvertAll method is called with the stringArray variable as the first argument and a lambda expression that calls the Int32.Parse method on each string value to convert them to integer values. The resulting int[] is stored in the intArray variable.

1. C# convert string to int

   string numberString = "42";
   int convertedInt = int.Parse(numberString);
   

2. C# convert string to double

   string numberString = "3.14";
   double convertedDouble = double.Parse(numberString);
   

3. Parsing string to float in C#

   string numberString = "3.14";
   float convertedFloat = float.Parse(numberString);
   

4. C# convert string to decimal

   string numberString = "123.45";
   decimal convertedDecimal = decimal.Parse(numberString);
   

5. Parsing string to long in C#

   string numberString = "123456789012345";
   long convertedLong = long.Parse(numberString);
   

6. C# convert string to short

   string numberString = "42";
   short convertedShort = short.Parse(numberString);
   

7. Parsing string to byte in C#

   string numberString = "255";
   byte convertedByte = byte.Parse(numberString);
   

8. C# convert string to uint

   string numberString = "4294967295";
   uint convertedUInt = uint.Parse(numberString);
   

9. Parsing string to ulong in C#

   string numberString = "18446744073709551615";
   ulong convertedULong = ulong.Parse(numberString);
   

10. C# convert string to ushort

    string numberString = "65535";
    ushort convertedUShort = ushort.Parse(numberString);
    

11. Parsing string to sbyte in C#

    string numberString = "-128";
    sbyte convertedSByte = sbyte.Parse(numberString);
    

12. Parsing string to nullable int in C#

    string numberString = "42";
    int? nullableInt = int.TryParse(numberString, out int result) ? result : (int?)null;
    

13. C# convert string to nullable double

    string numberString = "3.14";
    double? nullableDouble = double.TryParse(numberString, out double result) ? result : (double?)null;
    

14. Parsing string to nullable float in C#

    string numberString = "3.14";
    float? nullableFloat = float.TryParse(numberString, out float result) ? result : (float?)null;
    

15. C# convert string to nullable decimal

    string numberString = "123.45";
    decimal? nullableDecimal = decimal.TryParse(numberString, out decimal result) ? result : (decimal?)null;
    

16. Parsing string to nullable long in C#

    string numberString = "123456789012345";
    long? nullableLong = long.TryParse(numberString, out long result) ? result : (long?)null;
    

17. C# convert string to nullable short

    string numberString = "42";
    short? nullableShort = short.TryParse(numberString, out short result) ? result : (short?)null;
    

18. Parsing string to nullable byte in C#

    string numberString = "255";
    byte? nullableByte = byte.TryParse(numberString, out byte result) ? result : (byte?)null;