Handling Query String Parameters - (Web API Query String Parameters)

Web APIs allow clients to pass data to the server through query string parameters. In this tutorial, we'll discuss how to handle query string parameters in a Web API.

Syntax

To handle query string parameters in a Web API, you can use the FromQuery attribute in your API method parameter. Here's an example:

[HttpGet]
public IActionResult GetItems([FromQuery] string searchQuery)
{
    // logic to retrieve items based on searchQuery parameter
}

In this example, the GetItems API endpoint accepts a searchQuery parameter from the query string using the FromQuery attribute.

Example

Let's say we have a Web API that returns a list of items. We want to allow clients to search for items using a query string parameter called search. Here's how we can modify our GetItems API method to handle this parameter:

[HttpGet]
public IActionResult GetItems([FromQuery] string search)
{
    // logic to retrieve items based on search parameter
}

Now, clients can call the GetItems endpoint with the search query string parameter to receive a filtered list of items.

GET /api/items?search=example

Explanation

Query string parameters can be used to pass data to the server from the client. In a Web API, you can use the FromQuery attribute to indicate that a method parameter should come from the query string.

Use

Query string parameters are useful in Web APIs when clients need to pass data to the server in a simple and straightforward way. For example, you might use query string parameters to filter results or sort data.

Important Points

Here are some important points to keep in mind when handling query string parameters in a Web API:

• Always validate user input from query string parameters to prevent security issues.
• Be careful not to expose sensitive data through query string parameters.
• Use query string parameters sparingly, as they can clutter URLs and make them difficult to read.

Summary

In this tutorial, we discussed how to handle query string parameters in a Web API using the FromQuery attribute. We covered syntax, example, explanation, use, and important points of using query string parameters in a Web API. With this knowledge, you can create flexible and powerful Web APIs that accept query string parameters from clients.