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Each function coerces an expression (expression: Any combination of mathematical or logical operators, constants, functions, and names of fields, controls, and properties that evaluates to a single value. Expressions can perform calculations, manipulate characters, or test data.) to a specific data type (data type: The characteristic of a field that determines what type of data it can hold. Data types include Boolean, Integer, Long, Currency, Single, Double, Date, String, and Variant (default).).

**Syntax**

**CBool(***expression***)**

**CByte(***expression***)**

**CCur(***expression***)**

**CDate(***expression***)**

**CDbl(***expression***)**

**CDec(***expression***)**

**CInt(***expression***)**

**CLng(***expression***)**

**CSng(***expression***)**

**CStr(***expression***)**

**CVar(***expression***)**

The required ** expression** argument (argument: A value that provides information to an action, an event, a method, a property, a function, or a procedure.) is any string expression (string expression: An expression that evaluates to a sequence of contiguous characters. Elements of the expression can be: functions that return a string or a string

**Return Types**

The function name determines the return type as shown in the following:

Function |
Return Type |
Range for expression argument |
---|---|---|

CBool |
Boolean | Any valid string or numeric expression. |

CByte |
Byte | 0 to 255. |

CCur |
Currency | -922,337,203,685,477.5808 to 922,337,203,685,477.5807. |

CDate |
Date | Any valid date expression. |

CDbl |
Double | -1.79769313486231E308 to -4.94065645841247E-324 for negative values; 4.94065645841247E-324 to 1.79769313486232E308 for positive values. |

CDec |
Decimal | +/-79,228,162,514,264,337,593,543,950,335 for zero-scaled numbers, that is, numbers with no decimal places. For numbers with 28 decimal places, the range is +/-7.9228162514264337593543950335. The smallest possible non-zero number is 0.0000000000000000000000000001. |

CInt |
Integer | -32,768 to 32,767; fractions are rounded. |

CLng |
Long | -2,147,483,648 to 2,147,483,647; fractions are rounded. |

CSng |
Single | -3.402823E38 to -1.401298E-45 for negative values; 1.401298E-45 to 3.402823E38 for positive values. |

CStr |
String | Returns for CStr depend on the expression argument. |

CVar |
Variant | Same range as Double for numerics. Same range as String for non-numerics. |

**Remarks**

If the ** expression** passed to the function is outside the range of the data type being converted to, an error occurs.

In general, you can document your code using the data-type conversion functions to show that the result of some operation should be expressed as a particular data type rather than the default data type. For example, use **CCur** to force currency arithmetic in cases where single-precision, double-precision, or integer arithmetic normally would occur.

You should use the data-type conversion functions instead of **Val** to provide internationally aware conversions from one data type to another. For example, when you use **CCur**, different decimal separators, different thousand separators, and various currency options are properly recognized depending on the locale setting of your computer.

When the fractional part is exactly 0.5, **CInt** and **CLng** always round it to the nearest even number. For example, 0.5 rounds to 0, and 1.5 rounds to 2. **CInt** and **CLng** differ from the **Fix** and **Int** functions, which truncate, rather than round, the fractional part of a number. Also, **Fix** and **Int** always return a value of the same type as is passed in.

Use the **IsDate** function to determine if ** date** can be converted to a date or time.

**CDate** recognizes date formats according to the locale (locale: The set of information that corresponds to a given language and country.) setting of your system. The correct order of day, month, and year may not be determined if it is provided in a format other than one of the recognized date settings. In addition, a long date format is not recognized if it also contains the day-of-the-week string.

A **CVDate** function is also provided for compatibility with previous versions of Visual Basic. The syntax of the **CVDate** function is identical to the **CDate** function, however, **CVDate** returns a **Variant** whose subtype is **Date** instead of an actual **Date** type. Since there is now an intrinsic **Date** type, there is no further need for **CVDate**. The same effect can be achieved by converting an expression to a **Date,** and then assigning it to a **Variant**. This technique is consistent with the conversion of all other intrinsic types to their equivalent **Variant** subtypes.

** Note ** The **CDec** function does not return a discrete data type; instead, it always returns a **Variant** whose value has been converted to a **Decimal** subtype.

** Note ** Examples that follow demonstrate the use of this function in a Visual Basic for Applications (VBA) module. For more information about working with VBA, select **Developer Reference** in the drop-down list next to **Search** and enter one or more terms in the search box.

** Tip ** *T**he Expression Builder **with** IntelliSense** in** **Access 2010 helps with getting your **expression**s** r**ight**. **Read an article** or **try Office 2010*.

This example uses the **CBool** function to convert an expression to a **Boolean**. If the expression evaluates to a nonzero value, **CBool** returns **True**; otherwise, it returns **False**.

```
Dim A, B, Check
A = 5: B = 5 ' Initialize variables.
Check =
```**CBool(**A = B**)** ' Check contains True.
A = 0 ' Define variable.
Check = **CBool(**A**)** ' Check contains False.

This example uses the **CByte** function to convert an expression to a **Byte**.

```
Dim MyDouble, MyByte
MyDouble = 125.5678 ' MyDouble is a Double.
MyByte =
```**CByte(**MyDouble**)** ' MyByte contains 126.

This example uses the **CCur** function to convert an expression to a **Currency**.

```
Dim MyDouble, MyCurr
MyDouble = 543.214588 ' MyDouble is a Double.
MyCurr =
```**CCur(**MyDouble * 2**)**
' Convert result of MyDouble * 2 (1086.429176) to a
' Currency (1086.4292).

This example uses the **CDate** function to convert a string to a **Date**. In general, hard-coding dates and times as strings (as shown in this example) is not recommended. Use date literals and time literals, such as #2/12/1969# and #4:45:23 PM#, instead.

```
Dim MyDate, MyShortDate, MyTime, MyShortTime
MyDate = "February 12, 1969"
' Convert to Date data type.
MyShortDate =
```**CDate(**MyDate**)**
MyTime = "4:35:47 PM"
' Convert to Date data type.
MyShortTime = **CDate(**MyTime**)**

This example uses the **CDbl** function to convert an expression to a **Double**.

```
Dim MyCurr, MyDouble
MyCurr = CCur(234.456784)
' Convert result to a Double.
MyDouble =
```**CDbl(**MyCurr * 8.2 * 0.01**)**

This example uses the **CDec** function to convert a numeric value to a **Decimal**.

```
Dim MyDecimal, MyCurr
MyCurr = 10000000.0587 ' MyCurr is a Currency.
MyDecimal =
```**CDec(**MyCurr**)** ' MyDecimal is a Decimal.

This example uses the **CInt** function to convert a value to an **Integer**.

```
Dim MyDouble, MyInt
MyDouble = 2345.5678 ' MyDouble is a Double.
MyInt =
```**CInt(**MyDouble**)** ' MyInt contains 2346.

This example uses the **CLng** function to convert a value to a **Long**.

```
Dim MyVal1, MyVal2, MyLong1, MyLong2
MyVal1 = 25427.45
MyVal2 = 25427.55 ' MyVal1, MyVal2 are Doubles.
MyLong1 =
```**CLng(**MyVal1**)**
' MyLong1 contains 25427.
MyLong2 = **CLng(**MyVal2**)**
' MyLong2 contains 25428.

This example uses the **CSng** function to convert a value to a **Single**.

```
Dim MyDouble1, MyDouble2, MySingle1, MySingle2
' MyDouble1, MyDouble2 are Doubles.
MyDouble1 = 75.3421115: MyDouble2 = 75.3421555
MySingle1 =
```**CSng(**MyDouble1**)**
' MySingle1 contains 75.34211.
MySingle2 = **CSng(**MyDouble2**)**
' MySingle2 contains 75.34216.

This example uses the **CStr** function to convert a numeric value to a **String**.

```
Dim MyDouble, MyString
MyDouble = 437.324 ' MyDouble is a Double.
MyString =
```**CStr(**MyDouble**)**
' MyString contains "437.324".

This example uses the **CVar** function to convert an expression to a **Variant**.

```
Dim MyInt, MyVar
MyInt = 4534 ' MyInt is an Integer.
MyVar =
```**CVar(**MyInt & "000"**)**
' MyVar contains the string 4534000.