Type Conversions
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Implicit Conversion
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Explicit Conversion
Intro
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Value must be compatible with the variable.
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If not, we have to make a type conversion.
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Some data types can be converted to an other and
some can not.

We can lose data during unsafe conversion e.g.
assigning a floating point number to an integer. In
that case we lose fraction.
Implicit Conversions
Numeric
Numeric
Properties

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
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Occurs between compatible types.
Transfers data from a smaller type to a
bigger type.
No data loss.
No extra operation.
Automatic type conversion.
Compatible types
Example
Implicit Conversion
No data loss
Explicit Conversion
Numeric
Character
Character
Numeric
Properties

Occurs between incompatible types.

May lose data.

Extra coding needed.

Use with caution.
Example
Exercise

Assign a value to integer variable
“source” that can not fit in to short type.
Comment on the result.
Numeric

Character
.ToString() method.

Can be used with numeric types.

Converts numeric value to “string” type.
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There is also a formatting option.
Example
Output : 123
Formatting example
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“NumberFormatInfo” class.


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Used especially with floating point
numbers.
Resides under System.Globalization
namespace.
Formatting properties
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Number decimal digits
Number decimal separator
Number group separator
Formatting example
Output: 12.345,67
Character

Numeric
“Convert” class
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“Explicit Conversion”
Used in conversion of multiple types.
There should be compatible types between
conversions.
Example
Output: 132
Example – 2
Console.ReadLine()



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Used for getting input from screen.
String type value is returned.
Returns when user press Enter key.
Later, return value can be converted to
other types.
Console.ReadLine()