C# | Convert.ToInt32(String, IFormatProvider) Method

This method is used to converts the specified string representation of a number to an equivalent 32-bit signed integer, using the specified culture-specific formatting information.

Syntax:

public static int ToInt32 (string value, IFormatProvider provider);

Parameters:

• value: It is a string that contains the number to convert.
• provider: An object that supplies culture-specific formatting information.

Return Value: This method returns a 32-bit signed integer that is equivalent to the number in value, or 0 (zero) if value is null.

Exceptions:

• FormatException: If the value does not consist of an optional sign followed by a sequence of digits (0 through 9).
• OverflowException: If the value represents a number that is less than MinValue or greater than MaxValue.

Below programs illustrate the use of Convert.ToInt32(String, IFormatProvider) Method:

Example 1:

// C# program to demonstrate the
// Convert.ToInt32() Method
using System;
using System.Globalization;

class GFG {

// Main Method
public static void Main()
{
    try {

        // creating object of CultureInfo
        CultureInfo cultures = new CultureInfo("en-US");

        // declaring and initializing String array
        string[] values = {"12345", "+12345",
                                   "-12345"};

        // calling get() Method
        Console.Write("Converted int value "
                    + "of specified strings: ");

        for (int j = 0; j < values.Length; j++)
        {
            get(values[j], cultures);
        }
    }

    catch (FormatException e)
    {

        Console.WriteLine("\n");
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }

    catch (OverflowException e)
    {

        Console.WriteLine("\n");
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
}

// Defining get() method
public static void get(string s,
           CultureInfo cultures)
{

    // converting string to specified int
    int val = Convert.ToInt32(s, cultures);

    // display the converted char value
    Console.Write(" {0}, ", val);
}
}

Output:

Converted int value of specified strings:  12345,  12345,  -12345,

Example 2: For FormatException

// C# program to demonstrate the
// Convert.ToInt32() Method
using System;
using System.Globalization;

class GFG {

// Main Method
public static void Main()
{

try {

    // creating object of CultureInfo
    CultureInfo cultures = new CultureInfo("en-US");

    // declaring and initializing String array
    string[] values = {"12345", "+12345",
                              "-12345" };

    // calling get() Method
    Console.WriteLine("Converted int value"
              + " of specified strings: ");

    for (int j = 0; j < values.Length; j++)
    {

        get(values[j], cultures);
    }

    Console.WriteLine("\n");
    string s = "123 456, 789";

    Console.WriteLine("format of s is invalid ");

    // converting string to specified char
    int val = Convert.ToInt32(s, cultures);

    // display the converted char value
    Console.Write(" {0}, ", val);
}

catch (FormatException e) {

    Console.Write("Exception Thrown: ");
    Console.Write("{0}", e.GetType(), e.Message);
}
catch (OverflowException e) {

    Console.Write("Exception Thrown: ");
    Console.Write("{0}", e.GetType(), e.Message);
}
}

// Defining get() method
public static void get(string s,
           CultureInfo cultures)
{

// converting string to
// specified int value
int val = Convert.ToInt32(s, cultures);

// display the converted int value
Console.Write(" {0}, ", val);
}
}

Output:

Converted int value of specified strings: 
 12345,  12345,  -12345, 

format of s is invalid 
Exception Thrown: System.FormatException

Example 3: For OverFlowException

// C# program to demonstrate the
// Convert.ToInt32() Method
using System;
using System.Globalization;

class GFG {

// Main Method
public static void Main()
{

    try {

        // creating object of CultureInfo
        CultureInfo cultures = new CultureInfo("en-US");

        // declaring and initializing String array
        string[] values = {"12345", "+12345",
                                  "-12345" };

        // calling get() Method
        Console.WriteLine("Converted int value "
                    + "of specified strings: ");

        for (int j = 0; j < values.Length; j++)
        {

            get(values[j], cultures);
        }

        Console.WriteLine("\n");
        string s = "-7922816251426433759354395033500000";

        Console.WriteLine("s is less than the MinValue");

        // converting string to specified char
        int val = Convert.ToInt32(s, cultures);

        // display the converted char value
        Console.Write(" {0}, ", val);
    }

    catch (FormatException e)
    {
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }

    catch (OverflowException e)
    {
        Console.Write("Exception Thrown: ");
        Console.Write("{0}", e.GetType(), e.Message);
    }
}

// Defining get() method
public static void get(string s,
           CultureInfo cultures)
{

    // converting string to
    // specified int value
    int val = Convert.ToInt32(s, cultures);

    // display the converted int value
    Console.Write(" {0}, ", val);
}
}

Output:

Converted int value of specified strings: 
 12345,  12345,  -12345, 

s is less than the MinValue
Exception Thrown: System.OverflowException

Reference:

• https://docs.microsoft.com/en-us/dotnet/api/system.convert.toint32?view=netframework-4.7.2#System_Convert_ToInt32_System_String_System_IFormatProvider_