C＃检查引用是否为null - 运行时绑定错误

Question

我收到此错误：

Cannot perform runtime binding on a null reference

当我尝试将一个JSON对象分配给var

时

var vrlvl = dataFirst.payload.last_quick_matches.csgo.skill_level;

如何在分配对象之前检查对象是否为空？

我已尝试过这些，但它会出现同样的错误

if (dataFirst.payload.last_quick_matches.csgo.skill_level != null)

if (Object.ReferenceEquals(null, dataFirst.payload.last_quick_matches.csgo.skill_level)) 

Answer 1

您可能还需要检查几个级别：

if (dataFirst && dataFirst.payload && dataFirst.payload.last_quick_matches && dataFirst.payload.last_quick_matches.csgo && dataFirst.payload.last_quick_matches.csgo.skill_level)
{
    var vrlvl = dataFirst.payload.last_quick_matches.csgo.skill_level;
}

编辑：试试这个：

if (dataFirst != null && dataFirst.payload != null && dataFirst.payload.last_quick_matches != null && dataFirst.payload.last_quick_matches.csgo != null && dataFirst.payload.last_quick_matches.csgo.skill_level != null)
{
    var vrlvl = dataFirst.payload.last_quick_matches.csgo.skill_level;
}