- 错误 1 'int.TryParse(string, out int)' 的最佳重载方法匹配有一些无效参数
错误 2 参数 1:无法从“int”转换为“string”
它在“int.TryParse(surveys.First(), out id);”中给我错误
L var surveys = (from su in DbContext.Surveys where su.userName == su.userName select su.ID); if(surveys.Count() > 0) { int id = 0; int.TryParse(surveys.First(), out id); return id; } return 0;
最佳答案
从 TryParse() 中删除 int;
int.TryParse(surveys.First(), out int id);
应该是
int.TryParse(surveys.First(), out id);
改变:-
List<SurveyContext> surveys = (from su in DbContext.Surveys
where su.userName == su.userName
select su.ID).ToList();
到
List<string> surveys = (from su in DbContext.Surveys
where su.userName == su.userName
select su.ID);
您正在尝试选择 string
输入 Linq 并将其放入 List<SomeType>
应该是 List<int>
.
var surveys = (from su in DbContext.Surveys
where su.userName == su.userName
select su.ID);
//Code follows
int.TryParse(surveys.First(), out id);
关于c# - 代码中的无效表达式项错误,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/16680507/