# IsDate (str, strformat)

| **Name**    | ***IsDate (String)***                                                                                                                       |
| ----------- | ------------------------------------------------------------------------------------------------------------------------------------------- |
| Syntax      | IsDate (String str, String format)                                                                                                          |
| Purpose     | To check whether a given value represents valid date in the given format.                                                                   |
| Description | Returns true if the given value represents a valid date in the given format. Otherwise returns false.                                       |
| Return Type | Boolean                                                                                                                                     |
| Parameters  | <p>Str \[System.String] – Value to be Checked</p><p>Format \[System.string] – Format for parsing the string. Any valid .Net date format</p> |

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/0%20\(224\)%20\(1\).png)

**Example**

In this example, we will pass a valid *format* parameter and a string date parameter to match the given format, to the function transformation object using a *Variables* object.

Where,

*format* = yyyy-MM-dd

*str* = 2023-09-23

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/1%20\(224\)%20\(1\).png)

In the output, you can see that the Boolean value, True, has been returned. This means the provided value represents a valid date which matches the provided date format.

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/2%20\(222\)%20\(1\).png)


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