2条回答 默认 最新
- dream8877 2018-12-19 23:42关注
The value
nil
is not a valid value for astring
. If you want to fallback to the header on both missing values and empty values, then using the following code:params := r.URL.Query() tok := params.Get("x-huru-api-token") if tok == "" { tok = r.Header.Get("x-huru-api-token") }
If you only want to fallback to the header when the query parameter is missing, then use the following:
params := r.URL.Query() var tok string if values, ok := params["x-huru-api-token"]; ok && len(values) > 0 { tok = values[0] // note that tok can be the empty string "" } else { tok = r.Header.Get("x-huru-api-token") }
Note one difference between the code in this answer and the question. This answer uses assignment to set
tok
inside the if statement. The code in the question uses a short variable declaration. The short variable declaration will not compile because the newly declared variable inside the if statement is not used.本回答被题主选为最佳回答 , 对您是否有帮助呢?解决 无用评论 打赏 举报
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