Using Int.Parse() method
To convert string to int in C#. We can use the string representation of a number to its signed integer equivalent, Int.Parse() method.
We can use parse methods for 16, 32, 64 bit signed integer types.
The Parse() is the easiest way to convert from string to integer. It is also available for all the primitive datatypes.
C#
using System;
public class Example
{
public static void Main()
{
string str = "1000";
int num = Int32.Parse(str); // or, use `int.Parse()`
Console.WriteLine(num);
}
}
Output:
1000
The Int.Parse() method shows a FormatException if the string is not in the numeric form. We can also handle this using a try-catch block.
C#
using System;
public class Example
{
public static void Main()
{
string str = "1000";
try {
int num = Int32.Parse(str);
Console.WriteLine(num);
}
catch (FormatException) {
Console.WriteLine("Input string is invalid.");
}
}
}
Output:
1000
Advantages of the Parse() method
-
We can convert a valid numeric string to an integer value.
-
It supports different number styles.
- It also supports culture-specific custom formats.
Disadvantages of the Parse() method
-
The input string should be a valid integer string.
-
The numeric string should be within the range of the int type.
- It throws an exception while converting a null or invalid numeric string.
Using Int.TryParse() method
To convert string to int in C#. A better alternative to the Parse() method is to call the Int.TryParse() method. Comparing it to the Parse() method, it does not throw an exception if the conversion fails. If the conversion is failed, this method returns false.
The TryParse() method is recommended to convert a string to an integer. It is available for all the primitive types to convert string to the calling data type.
The TryParse() method converts the string representation to its 16, 32, and 64-bit signed integer equivalent. It returns a boolean indicating whether the conversion succeeded or failed, so it never throws exceptions.
C#
using System;
public class Example
{
public static void Main()
{
string str = "1000";
bool success = Int32.TryParse(str, out int num); // or, use `int.TryParse()`
if (success) {
Console.WriteLine(num);
}
else {
Console.WriteLine("Input string is invalid.");
}
}
}
Output:
1000
Advantages of the TryParse() method
-
We can convert different numeric strings to integers.
-
It converts the string representation of different number styles.
-
It can convert culture-specific numeric strings to integers.
- It never throws an exception. It will return false if it cannot parse to an integer.
Disadvantages of the TryParse() method
-
We must use parameters.
-
We need to write more code lines instead of single method calls.
- TryParse avoids the overhead of throwing exceptions on invalid input.
Using Convert.ToInt() method
The Convert.ToInt() method can convert a specified value to a signed integer.
Another way to convert string values to integers is using a static Convert class. The Convert class includes different methods that convert the base data type to another.
The Convert class has the following methods to convert different data types to int type.
C#
using System;
public class Example
{
public static void Main()
{
string str = "100s";
int num = Convert.ToInt32(str);
Console.WriteLine(num);
}
}
Output:
1000
Advantages of Convert.ToInt() method
-
We can convert from any data type to an integer.
-
We can also convert null to 0. We can do it by not throwing an exception.
- Works well for the string in general.
Disadvantages of Convert.ToInt() method
-
The input string must be a valid number string and cannot include different numeric formats. It only works with valid integer strings.
-
The input string must be within the range. It is called IntXX method ,e.g. Int16, Int32, Int64.
-
The input string cannot include parenthesis, commas, etc.
-
It must use a different method for different integer ranges. For example, we cannot use the Convert.ToInt16() for the number string higher than "32767".
Check out this problem - Longest String Chain
Frequently Asked Questions
How to convert a number in a string to an int in C#?
To convert a number in a string to an int in C#, you can use int.Parse() or int.TryParse() methods. int.Parse() directly converts, while int.TryParse() is safer, returning a boolean for success and storing the result in an out parameter, avoiding exceptions for invalid input strings.
How to convert a string to an int Java?
In Java, convert a string to an int using Integer.parseInt() or Integer.valueOf(). Both methods parse the string representation of a number. parseInt() returns a primitive int, while valueOf() returns an Integer object, allowing for additional operations with Java's Integer class.
How to convert string to int list in C#?
To convert a string to an int list in C#, use LINQ's Select method along with int.Parse or int.TryParse. For example, List<int> intList = str.Split(','). Select(int.Parse).ToList(); splits the string by commas and converts each part to an int, creating an integer list.
How to convert bit string to int in C#?
To convert a bit string to an int in C#, use Convert.ToInt32(string, 2). The second argument, "2", indicates that the string is in binary format. This method parses the binary string and returns its integer representation.
Conclusion
This article briefly discussed how to convert string to int in C#. We discussed various methods such as Parse(), TryParse(), and Convert.ToInt(). We also discussed their pros and cons, thus concluding our discussion of how to convert string to int in C#
We hope that this blog has helped you enhance your knowledge about the topic of how to convert string to DateTime in C#. If you like to learn more, you can check out our articles:
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