正在尝试将非空字符串设置为System.Int32&#39；类型

问题描述

实体框架引发此异常：

它在这条线上抛出：

// Validate uniqueness or email and username
var user = sqlStorage.BranchIdentities.FirstOrDefault(i => i.Username.ToLower() == viewModel.Username.ToLower());

仅当存在与查询匹配的实体时才引发异常。如果没有匹配项，则不会引发异常。

我的BranchIdentity模型：

namespace Branch.Models.Sql
{
    public class BranchIdentity
    {
        [Key]
        public int Id { get; set; }

        [Required]
        public string Username { get; set; }

        [Required]
        public string PasswordHash { get; set; }

        [Required]
        public string PasswordSalt { get; set; }

        [Required]
        public int PasswordIterations { get; set; }

        [Required]
        public string Email { get; set; }

        [Required]
        public string FullName { get; set; }

        public virtual ICollection<BranchIdentitySession> BranchIdentitySessions { get; set; } 

        public virtual BranchRole BranchRole { get; set; }

        public virtual GamerIdentity GamerIdentity { get; set; }
    }
}

和我的架构(取自SQL数据库)-使用代码优先迁移自动生成：

CREATE TABLE [dbo].[BranchIdentities] (
    [Id]                 INT            IDENTITY (1, 1) NOT NULL,
    [Username]           NVARCHAR (MAX) NOT NULL,
    [PasswordHash]       NVARCHAR (MAX) NOT NULL,
    [PasswordSalt]       NVARCHAR (MAX) NOT NULL,
    [PasswordIterations] INT            NOT NULL,
    [Email]              NVARCHAR (MAX) NOT NULL,
    [BranchRole_Id]      INT            NULL,
    [GamerIdentity_Id]   INT            NULL,
    [FullName]           NVARCHAR (MAX) DEFAULT ('') NOT NULL,
    CONSTRAINT [PK_dbo.BranchIdentities] PRIMARY KEY CLUSTERED ([Id] ASC),
    CONSTRAINT [FK_dbo.BranchIdentities_dbo.BranchRoles_BranchRole_Id] FOREIGN KEY ([BranchRole_Id]) REFERENCES [dbo].[BranchRoles] ([Id]),
    CONSTRAINT [FK_dbo.BranchIdentities_dbo.GamerIdentities_GamerIdentity_Id] FOREIGN KEY ([GamerIdentity_Id]) REFERENCES [dbo].[GamerIdentities] ([Id])
);

我已尝试使PasswordIterations可为Null，但无济于事。

推荐答案

仅供有此问题的其他人使用。在DatabaseContext中设置断点，并确保它连接到正确的数据库。我的文件被我忘记的一个web.config文件覆盖了。