What are the different assignment operators in PHP, how do they differ [duplicate]

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Reference - What does this symbol mean in PHP?

I have seen referenc开发者_Python百科es to = (of course) but also .= and ^=. What are those two for? Are there others?

^= is a bitwise operator and .= is a string operator. Both are assignment operators, as they set the value of a variable after evaluating.

The former sets the value of the variable to a XOR of the expression. The latter concats the expression onto the variable.

Many of the binary operators (e.g. +, -, *, /) can be used in conjunction with = as shorthand for assigning values. Essentially, x += 4 is equivalent to x = x + 4.