What is the usage of php for statement

Usage of php for statement: first set the initial value of some counter variables; then check that the conditional statement is correct, and then execute the intermediate code loop; finally, the increment passes through the loop counter at the end of each iteration.

php for statement usage:

The for loop is just a little more code, while the loop is added to it . The common task of a loop involved is:

• Set the initial value of some counter variables.

• Please check that the conditional statement is correct.

• Code loop during execution.

• Increment the loop counter at the end of each iteration.

• The for loop allows you to define these steps with a simple line of code. It seems to have a strange form, so be sure to pay close attention to the grammar!

The syntax of the for loop is:

for (expr1; expr2; expr3) 
statement

• The first expression (expr1) is unconditional before the loop starts Evaluate once.

• #expr2 is evaluated before each loop. If the value is TRUE, the loop continues and the nested loop statement is executed. If the value is FALSE, the loop is terminated.

• #expr3 is evaluated (executed) after each loop.

Each expression can be empty or include multiple expressions separated by commas. In the expression expr2, all comma-separated expressions are evaluated, but only the last result is taken. An empty expr2 means that the loop will continue indefinitely (like C, PHP considers its value to be TRUE). This may not be as useless as you think, because you often want to use a break statement to end the loop instead of using the for expression truth check.

Look at a simple example

The code is as follows:

FOR ($i = 0; $i <= 2; $i++) 
{ 
print "value is now " . $i . "<br>"; 
}

Output value

value is now 0 
value is now 1 
value is now 2

In the first loop, $i=0, This means that the expression, ($i<= 2), is true. Therefore, when the print statement is executed, $i is incremented by 1 and becomes 1.

In the second loop, $ = 1, which means that the expression, ($i<= 2), is true. Therefore, when the print statement is executed, $i is incremented by 1 and becomes 2.

In the third iteration, $i= 2, which means that the expression, ($i<= 2), is true. Therefore, when the print statement is executed, $i is incremented and becomes 1 3.

In the fourth iteration, $i= 3, which means that the expression, ($i<= 2), is false. Therefore, PHP does not execute the loop and does not execute the print statement.

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