我的代码：
private void btnLogin_Click(object sender, EventArgs e)
{
if (this.txtUserName.Text == "" || this.txtPassword.Text == "")
{
MessageBox.Show("Credentials are missing...", clsVariables._strProjectName, MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else
{
string _strQuery = "SELECT AtNumConstructorID, TxtConstructorName AS Fullname, tblConstructorDetails.txtUserName FROM tblConstructorDetails WHERE txtUserName = '" + this.txtUserName.Text + "' AND TxtPassword LIKE '" + this.txtPassword.Text + "' ";
if (clsFunctions.recordExist(_strQuery, "tblConstructorDetails") == true)
{
clsVariables._sTimeLogin = DateTime.Now.ToLongTimeString();//recording the time of login in the CES
long totalRow = 0;
//Set the Data Adapter
OleDbDataAdapter da = new OleDbDataAdapter(_strQuery, clsConnections._olbedbCN);
DataSet ds = new DataSet(); // creating a dataset to enter the values in the dataadapter
da.Fill(ds, "tblConstructorDetails");
totalRow = ds.Tables["tblConstructorDetails"].Rows.Count - 1;
clsVariables._sContId = Convert.ToInt32(ds.Tables["tblConstructorDetails"].Rows[0].ItemArray.GetValue(0));
clsVariables._sConstructor = ds.Tables["tblConstructorDetails"].Rows[0].ItemArray.GetValue(1).ToString();
clsVariables._sUserID = ds.Tables["tblConstructorDetails"].Rows[0].ItemArray.GetValue(2).ToString();
clsUserLogs.RecordLogin(clsVariables._sTimeLogin, clsVariables._sContId);
clsApplication._boolAPP_CONNECTED = true;
this.Close();
}
#region trash code 2
/*string _strUsername = this.txtUserName.Text.Trim();
string _strPassword = txtPassword.Text;
string _strSQL = "select * from tblConstructorDetails where Upper(TxtUserName) = '" + _strUsername.ToUpper() +"' and TxtPassword = '" + _strPassword + "'";
if ()
{
} */
#endregion
else
{
clsVariables._intAttempt--;
if (clsVariables._intAttempt > 0)
{
MessageBox.Show("Login failed. Please try again. Only " + Convert.ToString(clsVariables._intAttempt) + " attempts remaining...", "Login Failed", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else
{
MessageBox.Show("Exiting the system", clsVariables._strProjectName, MessageBoxButtons.OK);
this.Close();
}
}
}
}
#endregion
recordExist的代码：
#region Filters the records if exists in the table
//Filter if Recort is Exist in the Table.
public static bool recordExist(string _sSQL, string _sTable)
{
long totalRow = 0;
//Set the Data Adapter
OleDbDataAdapter _oledbAdDa = new OleDbDataAdapter(_sSQL, _olbedbCN);
DataSet _ds = new DataSet();
_oledbAdDa.Fill(_ds, _sTable);
totalRow = Convert.ToInt32(_ds.Tables[_sTable].Rows.Count);
if (totalRow > 0) { return true; }
else { return false; }
}
#endregion
我面临的问题是，当我尝试在相应的文本框中输入值时，这些值未传递给查询以检查登录是否可用....
请检查一下，并向我提供可能的解决方案和原因，为什么会发生这件事......
提前完成了......
答案 0 :(得分：0)
您可能希望从
更改sql中的字符串比较运算符=
到
LIKE
我觉得你错过了问你的问题，而且问题是sql返回没有数据。
string _strQuery = "SELECT AtNumConstructorID, TxtConstructorName AS Fullname, tblConstructorDetails.txtUserName FROM tblConstructorDetails WHERE txtUserName LIKE '"
+ this.txtUserName.Text + "' AND TxtPassword LIKE '" + this.txtPassword.Text + "' ";
更改正好在第一行的第二行。