Question

尝试从C＃Winforms项目执行以下过程时，我收到以下错误：

从字符串
转换日期和/或时间时转换失败

这是我的存储过程：

CREATE PROCEDURE DisplayTime  
    @name VARCHAR(50),  
    @fromdate date,    
    @todate date  
AS  
BEGIN  
    DECLARE @VTIME  TIME(7)   

    SELECT 
        @VTIME = CAST(SUM(DATEDIFF(SECOND, 0, time)) /60/60 AS TIME)   
            +':'+CAST(SUM(DATEDIFF(SECOND, 0, time)) /60%60 AS TIME)   
            +':'+ CAST(SUM(DATEDIFF(SECOND, 0, time)) % 60 AS TIME)  
    FROM
        (SELECT time 
         FROM time 
         WHERE [user] = '@name' 
           AND date BETWEEN '@fromdate' AND '@todate') AS T

    SELECT @VTIME AS count_down_sec
END

这是我的C＃代码：

private void button1_Click(object sender, EventArgs e)  
{  
    if (txt_UserName.Text != "")  
    {  
        con.Open();  
        cmd = new SqlCommand("DisplayTime",con);  
        cmd.CommandType = CommandType.StoredProcedure;  

        cmd.Parameters.AddWithValue("@name", txt_UserName.Text);  
        cmd.Parameters.AddWithValue("@fromdate",dateTimePicker1.Value.Date);  
        cmd.Parameters.AddWithValue("@todate",dateTimePicker2.Value.Date);  

        cmd.ExecuteNonQuery();  
        con.Close();  

        MessageBox.Show(txtTotal.Text);  
    }  
}

Answer 1

不确定您在此过程中尝试执行的操作。但是，除非您使用，否则参数名称不必用单引号括起来 Execute()。删除@ name，@ fromdate和@todate

周围的引号

此外，您需要提供正确的命名，以便其他开发人员不会与数据类型名称和列/表名称混淆。

CREATE PROCEDURE DisplayTime  
@name VARCHAR(50),  
@fromdate date,    
@todate date  
AS  
BEGIN  
DECLARE @VTIME  TIME(7)   

SELECT 
    @VTIME = CAST(SUM(DATEDIFF(SECOND, 0, time)) /60/60 AS TIME)   
        +':'+CAST(SUM(DATEDIFF(SECOND, 0, time)) /60%60 AS TIME)   
        +':'+ CAST(SUM(DATEDIFF(SECOND, 0, time)) % 60 AS TIME)  
FROM
    (SELECT time 
     FROM time 
     WHERE [user] = @name
       AND date BETWEEN @fromdate AND @todate) AS T

SELECT @VTIME AS count_down_sec
END

从字符串SQL Server存储过程转换日期和/或时间时转换失败

1 个答案: