查询字符串构建器

from urllib.parse import urlencode, urlparse, parse_qs, urljoin

# Build a query string from a dict
params = {
    "q":       "hello world",
    "lang":    "en",
    "page":    "2",
    "filter":  "price>100&color=red",  # special chars auto-encoded
}
qs = urlencode(params)
print("Query string:", qs)
# q=hello+world&lang=en&page=2&filter=price%3E100%26color%3Dred

# Append to a base URL
base_url = "https://example.com/search"
full_url = f"{base_url}?{qs}"
print("Full URL:    ", full_url)

# Parse a query string back to a dict
parsed = parse_qs("q=hello+world&lang=en&page=2")
print("Parsed:      ", parsed)
# {'q': ['hello world'], 'lang': ['en'], 'page': ['2']}

# Parse an existing URL
url = "https://example.com/search?q=test&page=1#results"
parts = urlparse(url)
params_back = parse_qs(parts.query)
print("Params from URL:", params_back)