Question

I am trying to get a string value like below

string bsgrpval;
bsgrpval =
    ConfigurationSettings.AppSettings["Pricing_IncludeALLBaseLineGroup"]=="False"
        ? string.Empty
        : bsgrp.ForEach(x => bsgrpval = bsgrpval + x.Value.ToString() + ",");

我正在经历以下错误:

Type of conditional expression cannot be determined because there is no implicit conversion between string and void

有些人能够帮助我这样做?

Answer 1

如果这样的话,你就能够直截了当。 List.ForEach 根本不归还。

condition ? x : y;

<代码>x和y> ,必须交回同一类型(或含蓄)。

也许,你希望有一席之地。

bsgrpval = ConfigurationSettings.AppSettings["Pricing_IncludeALLBaseLineGroup"]=="False"
        ? string.Empty
        : string.Join( , , 
             bsgrp.Select(x => bsgrpval = bsgrpval + x.Value.ToString()).ToArray());

Answer 2

错误发生是因为<代码>。每一条都有固定回报。页: 1 Aggregate :

string bsgrpval;  
bsgrpval=ConfigurationSettings.AppSettings["Pricing_IncludeALLBaseLineGroup"] == "False" string.Empty : bsgrp.Aggregate((acc, item) => string.Concat(acc, ",", item.Value.ToString()));

友情链接