requestHeaders 常量
实现
static const requestHeaders = [
acceptHeader,
acceptCharsetHeader,
acceptEncodingHeader,
acceptLanguageHeader,
authorizationHeader,
expectHeader,
fromHeader,
hostHeader,
ifMatchHeader,
ifModifiedSinceHeader,
ifNoneMatchHeader,
ifRangeHeader,
ifUnmodifiedSinceHeader,
maxForwardsHeader,
proxyAuthorizationHeader,
rangeHeader,
refererHeader,
teHeader,
userAgentHeader
];