JavaScript中try...catch和异常处理
在JavaScript可以使用try...catch来进行异常处理。例如:
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目前我们可能得到的系统异常主要包含以下6种:
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上面的六种异常对象都继承自Error对象。他们都支持以下两种构造方法:
new Error();
new Error( " 异常信息 " );
手工抛出异常的方法如下:
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如要判断异常信息的类型,可在catch中进行判断:
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Error具有下面一些主要属性:
description: 错误描述 (仅IE可用).
fileName: 出错的文件名 (仅Mozilla可用).
lineNumber: 出错的行数 (仅Mozilla可用).
message: 错误信息 (在IE下同description)
name: 错误类型.
number: 错误代码 (仅IE可用).
stack: 像Java中的Stack Trace一样的错误堆栈信息 (仅Mozilla可用).
因此为了更好的了解错误信息我们可以将catch部分改为如下形式:
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JavaScript中的throw命令事实上可以抛出任何对象,并且我们可以在catch接受到此对象。例如:
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try {
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throw new Date(); // 抛出当前时间对象
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} catch (e) {
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alert(e.toLocaleString()); // 使用本地格式显示当前时间
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}
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