C# 检查整型数据集值是否返回dbnull值
我在检查返回的值在C#中是否有DBnull值时遇到问题 这是我的密码C# 检查整型数据集值是否返回dbnull值,c#,asp.net,C#,Asp.net,我在检查返回的值在C#中是否有DBnull值时遇到问题 这是我的密码 LoanDSTableAdapters.LoanApplicationsTableAdapter loanApp = new LoanDSTableAdapters.LoanApplicationsTableAdapter(); LoanDS.LoanApplicationsDataTable loanAppDetails = loanApp.GetLoanApplication(MySessionMan
LoanDSTableAdapters.LoanApplicationsTableAdapter loanApp =
new LoanDSTableAdapters.LoanApplicationsTableAdapter();
LoanDS.LoanApplicationsDataTable loanAppDetails =
loanApp.GetLoanApplication(MySessionManager.AppID.ToString());
if (loanAppDetails.Rows.Count > 0)
{
int newclient;
if (!loanAppDetails[0].datNewClient == DBNull.Value)
{
newclient = 1;
}
else
{
newclient = Convert.ToInt32(loanAppDetails[0].datNewClient.ToString());
}
这是我犯的错误,让我发疯:
运算符“!”不能应用于“int”类型的操作数
正如Uwe所说,你需要提高你的c#技能
这是一条路要走。相反,您告诉编译器对int求反,然后将其与DbNull进行比较——这是不可能的。不要发疯。尝试了解。换句话说:使用例如
loanAppDetails[0]。datNewClient!=DBNull.Value
。或使用!(loanAppDetails[0].datNewClient==DBNull.Value)
。谢谢大家!它起作用了
if (loanAppDetails[0].datNewClient != DBNull.Value)