Possible Duplicate: Whats the main difference between int. Parse and Convert. ToInt converts an object to an integer and returns 0 if the value was null. Parse convert a string to an integer and throws an exception if the value wasn't able to convert.
ToInt32 will return 0 if the input string is null. Parse will throw an exception. To s doesn't throw an exception when argument is null, but Parse does. To s returns 0 when argument is null. Parse and Int. TryParse can only convert strings. To s can take any class that implements IConvertible.
Hence, Convert. To s is probably a wee bit slower than Int. Parse because it has to ask its argument what it's type is. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. A bit signed integer that is equivalent to the number in value , or 0 zero if value is null. The exception message indicates that there are no digits to convert if the first character in value is invalid; otherwise, the message indicates that value contains invalid trailing characters.
The following example attempts to interpret each element in a string array as a hexadecimal string and to convert it to a bit signed integer. If fromBase is 16, you can prefix the number specified by the value parameter with "0x" or "0X". Because the negative sign is not supported for non-base 10 numeric representations, the ToInt16 String, Int32 method assumes that negative numbers use two's complement representation.
In other words, the method always interprets the highest-order binary bit of an integer bit 15 as its sign bit. As a result, it is possible to write code in which a non-base 10 number that is out of the range of the Int16 data type is converted to an Int16 value without the method throwing an exception.
The following example increments Int MaxValue by one, converts the resulting number to its hexadecimal string representation, and then calls the ToInt16 String, Int32 method.
Instead of throwing an exception, the method displays the message, "0x converts to When performing binary operations or numeric conversions, it is always the responsibility of the developer to verify that a method is using the appropriate numeric representation to interpret a particular value.
As the following example illustrates, you can ensure that the method handles overflows appropriately by first retrieving the sign of the numeric value before converting it to its hexadecimal string representation.
Throw an exception if the original value was positive but the conversion back to an integer yields a negative value. The following example converts string representations of bit integers with the ToInt16 method, using an IFormatProvider object. The NumberFormatInfo object provides culture-specific information about the format of value. If provider is null , the NumberFormatInfo for the current culture is used. If you prefer not to handle an exception if the conversion fails, you can call the Int TryParse method instead.
It returns a Boolean value that indicates whether the conversion succeeded or failed. An object that implements the IConvertible interface. A bit signed integer that is equivalent to value , or zero if value is null. The following example defines a class that implements IConvertible and a class that implements IFormatProvider. Objects of the class that implements IConvertible hold an array of Double values. An object of each class is passed to the ToInt16 method.
This method returns an average of the array of Double values, using the object that implements IFormatProvider to determine how to calculate the average. For example, if value is a String that represents a number, provider could supply culture-specific information about the notation used to represent that number.
The base types ignore provider ; however, the parameter may be used if value is a user-defined type that implements the IConvertible interface. A bit signed integer that is equivalent to value. The following example attempts to convert each element in an array of unsigned long integers to a bit signed integer.
The following example attempts to convert each element in an array of unsigned integers to a bit signed integer. The following example attempts to convert each element in an array of unsigned bit integers to a bit signed integer. The following example converts string representations of bit integers with the ToInt16 method, using default formatting.
Parse throws an ArgumentNullException Use Convert class when you convert object type that contains type in which you want to convert.
For example when you execute ExecuteScalar of SqlDataReader it will return object type result but you know which type of object you expect and you use Convert. ToInt32, Convert. ToString or some other, to get the value. Same is when you want to get SelectedItem of the combo which is of type object but contains string and you need to use Convert. ToString to get the selected value.
Parse or 'type'. TryParse can be used only when converting string which contain targeted value type. Nikhil Mahajan replied to madhu krishna on Apr AM. Ravi S replied to madhu krishna on Apr AM. Hi Madhu Int Parse string s method converts the string representation of a number to its bit signed integer equivalent.
When s is a null reference, it will throw ArgumentNullException. If s is other than integer value, it will throw FormatException. ToInt32 string Convert. ToInt32 string s method converts the specified string representation of bit signed integer equivalent.
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