Subversive function, how to use filter

For PHP developers, the function filter_var() is undoubtedly a disruptive tool. Through the filter_var() function, we can easily filter and verify user input data, effectively preventing malicious input. In actual projects, how to use the filter_var() function correctly has become an important issue. This article will discuss this topic to help readers better master the usage skills of the filter_var() function. Here, PHP editor Strawberry will explain in detail the various application scenarios and precautions of the filter_var() function, allowing you to easily control this powerful function.

Let's first take a look at its structure. The filter function contains three parameters - "data", "includes" and "returns if empty".

1. Let’s take the following figure as an example to better understand this function.

2. Suppose we need to query the employment status, click the first cell under "Department", as shown in the figure:

3. Enter the formula (don’t forget to enter “=" first), as shown in the picture:

4. Enter the parameters.

The array is the entire data area. We can directly use the mouse to select the frame, as shown in the figure:

Includes the conditions that need to be queried, that is Working status, select the box, then enter "=", and then click the "Working" cell, as shown in the picture:

5. Press the Enter key. You can see that the data is displayed, as shown in the figure:

If the filtering conditions become multiple, we need to slightly modify the function and combine the second condition with The first condition becomes a multiplication relationship and is added to it, as shown in the figure:

If you want to get information about multiple conditions, for example, you want to get "Production Department" and For the employee information of the two departments of "Sales Department", just use " " to link the two "includes", as shown in the figure: How about

, there are Don’t you feel like you’ve gained a lot of posture? The emergence of the Filter function can be said to save a lot of troublesome work and is very powerful. Wouldn't it be very useful if you master this skill proficiently. What are you waiting for, hurry up and start practicing!

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