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1. What is the need for ‘Conversion of data type’ in C#?
a) To store a value of one data type into a variable of another data type
b) To get desired data
c) To prevent situations of runtime error during change or conversion of data type
d) None of the mentioned

2. Types of ‘Data Conversion’ in C#?
a) Implicit Conversion
b) Explicit Conversion
c) Implicit Conversion and Explicit Conversion
d) None of the mentioned

3. ‘Implicit Conversion’ follows the order of conversion as per compatibility of data type as:
a) float < char < int
b) char < int < float
c) int < char < float
d) float < int < char

4. For the following C# code select the relevant solution for conversion of data type.

```
 static void Main(string[] args)
```
```
 {
```
```
     int num1 = 20000;
```
```
     int num2 = 50000;
```
```
     long total;
```
```
     total = num1 + num2;
```

     Console.WriteLine("Total is : " +total);

```
     Console.ReadLine();
```
```
 }
```

a) Compiler will generate runtime error
b) Conversion is implicit type, no error generation
c) Specifying data type for conversion externally will solve the problem
d) None of the mentioned

Answer: b
Explanation: Since,conversion of data type is implicit type as ‘int’ is a subset of ‘longtype’ hence no need to explicitly convert data from one type to another.Compiler will automatically do conversion.
Output: Total is:

70000.

5. The subset of ‘int’ data type is __________
a) long, ulong, ushort
b) long, ulong, uint
c) long, float, double
d) long, float, ushort

6. Type of Conversion in which compiler is unable to convert the data type implicitly is?
a) ushort to long
b) int to uint
c) ushort to long
d) byte to decimal

7. Disadvantages of Explicit Conversion are?
a) Makes program memory heavier
b) Results in loss of data
c) Potentially Unsafe
d) None of the mentioned

```
 static void Main(string[] args)
```
```
 {
```
```
     int a = 76;
```
```
     char b;
```
```
     b = (char)a;
```
```
     Console.WriteLine(b);
```
```
     Console.ReadLine();
```
```
 }
```

a) Compiler will generate runtime error
b) Conversion is explicit type
c) Compiler will urge for conversion from ‘integer’ to ‘character’ data type
d) None of the mentioned

Answer: b
Explanation: Since, given conversion is of explicit type as one data type is in integer and other is in ‘char’. Compiler is needed to make a clear distinction between both type of data types and hence, explicitly one need to specify data type as compiler is unable to make automatic conversion.
Output :

L.

```
static void Main(string[] args)
```
```
{
```
```
    float sum;
```
```
    int i;
```
```
    sum = 0.0F;
```
```
    for (i = 1; i <= 10; i++)
```
```
    {
```
```
        sum = sum + 1 /(float)i;
```
```
    }
```
```
    Console.WriteLine("sum =" +sum);
```
```
    Console.ReadLine();
```
```
}
```

Answer: c
Explanation: None.
Output :

 sum = 2.928698.

```
 static void Main(string[] args)
```
```
 {
```
```
     int a = 22;
```
```
     long b = 44;
```
```
     double c = 1.406;
```
```
     b = a;
```
```
     c = a;
```
```
     a = b;
```
```
     b = c;
```
```
 }
```

Answer: a
Explanation: Conversion of data type from ‘int’ to ‘double’ is implicit in nature for ‘c = a’ as int is subset of double but same is not applicable for ‘b = c’ as ‘c’ had wider scope of data range then ‘b’ so explicit conversion is needed.
Output :

 Error 1: Can not implicitly convert type 'long' to 'int'. An explicit conversion exists (are you missing a cast?).	
 Error 2: Cannot implicitly convert type 'double' to 'long'. An explicit conversion exists (are you missing a cast?).	
 
 Correct solution :

 static void Main(string[] args)
 {
     int a = 22;
     long b = 44;
     double c = 1.406;
     b = a;
     c = a;
     a = (int)b;
     b = (long)c;
 }

C# Questions & Answers –Type Conversion in Expressions