jquery - 在函数外使用变量
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jquery - use a variable outside the function
提问by user705730
How I Can use a variable outside the function where it was declared?
如何在声明它的函数之外使用变量？
$(function() {
function init() {
var bwr_w = $(window).width();
}
init();
$('#button').click(function() {
alert('The Browser Height is' + bwr_w);
});
});
If I click on the button I get this error:
如果我单击按钮，则会收到此错误：
bwr_w is not defined
bwr_w 未定义
回答by Matías Fidemraizer
Just declare that variable in constructor's scope:
只需在构造函数的范围内声明该变量：
$(function() {
var bwr_w = null;
function init() {
bwr_w = $(window).width();
}
init();
$('#button').click(function() {
alert('The Browser Height is' + bwr_w);
});
});
回答by Andrei Andrushkevich
try this
尝试这个
$(function() {
var bwr_w = 0;
function init() {
bwr_w = $(window).width();
}
init();
$('#button').click(function() {
alert('The Browser Height is' + bwr_w);
});
});
回答by David says reinstate Monica
If you declare the variable outside the function, then assign a value to it insidethe function, it should be accessible elsewhere. So long as you're sure that a value will be assigned. If you're not sure, you might want to assign a default value:
如果在函数外部声明变量，然后在函数内部为其赋值，则应该可以在其他地方访问它。只要您确定将分配一个值。如果您不确定，您可能需要指定一个默认值：
$(function() {
var bwr_w; // or 'var bwr_w = default_value;'
function init() {
bwr_w = $(window).width();
}
init();
$('#button').click(function() {
alert('The Browser Height is' + bwr_w);
});
});
