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    block

    Summary

    Block digunakan untuk mengelompokkan 0 atau lebih statement. Block dibuka dan ditutup oleh sepasang { }.

    Version Information

    Statement
    Implemented in: JavaScript 1.0, NES 2.0
    ECMA Version: ECMA-262

    Syntax

    {
       statement_1
       statement_2
       ...
       statement_n
    }
    

    Parameters

    statement_1, statement_2, statement_n
    Statements grouped within the block statement.

    Description

    This statement is commonly used with control flow statements (e.g. if, for, while). For example:

    while (x < 10) {
       x++;
    }
    

    Important: JavaScript does not have block scope. Variables introduced with a block are scoped to the containing function or script, and the effects of setting them persist beyond the block itself. In other words, block statements do not introduce a scope. Although "standalone" blocks are valid syntax, you do not want to use standalone blocks in JavaScript, because they don't do what you think they do, if you think they do anything like such blocks in C or Java. For example:

    var x = 1;
    {
       var x = 2;
    }
    alert(x); // outputs 2
    

    This outputs 2 because the var x statement within the conditional is in the same scope as the var x statement before the conditional. In C or Java, the equivalent code would have outputted 1.

    Document Tags and Contributors

    Contributors to this page: keripix, teoli
    Last updated by: teoli,