Optimize the code

regist.cpp

@@ -34,6 +34,8 @@ void Regist::on_pushButton_clicked()
         return;
     }
     QMessageBox::about(this,"提示","注册成功");
+    this->parentWidget()->show();
+    this->hide();
 }
 
 void Regist::on_goback_clicked()

userwindow.cpp

@@ -46,8 +46,12 @@ void UserWindow::on_find_usr_clicked()
     bool ok;
     QString text = QInputDialog::getText(this, tr("查询"),
                                  tr("查找用户"), QLineEdit::Normal,
-                                 tr("请输入用户名"), &ok);
+                                 tr(""), &ok);
     if (ok) {
+        if (text.isEmpty()) {
+            QMessageBox::warning(this, "提示", "请输入需要查找的用户!", QMessageBox::Ok);
+            return;
+        }
         QString str = QString("SELECT * FROM user WHERE username = '%1'").arg(text);
         QSqlQuery query(QSqlDatabase::database("HB"));
         if (!query.exec(str)) {
@@ -81,8 +85,12 @@ void UserWindow::on_delet_usr_clicked()
     bool ok;
     QString text = QInputDialog::getText(this, tr("删除用户"),
                                  tr("查找用户"), QLineEdit::Normal,
-                                 tr("请输入用户名"), &ok);
+                                 tr(""), &ok);
     if (ok) {
+        if (text.isEmpty()) {
+            QMessageBox::warning(this,"提示","输入为空",QMessageBox::Ok);
+            return;
+        }
         QString str = QString("DELETE FROM user WHERE username = '%1'").arg(text);
         QSqlQuery sql_query(db);
         if (!sql_query.exec(str)) {
@@ -107,16 +115,23 @@ void UserWindow::on_updata_usr_clicked()
     bool ok;
     QString text = QInputDialog::getText(this, tr("修改用户信息"),
                                  tr("查找用户"), QLineEdit::Normal,
-                                 tr("请输入需要修改的用户"), &ok);
+                                 tr(""), &ok);
     if (ok) {
+        if (text.isEmpty()) {
+            QMessageBox::warning(this,"提示","输入为空",QMessageBox::Ok);
+            return;
+        }
         int ret = QMessageBox::question(this, tr("修改选项"),
                                            "修改用户名/密码？(Yes-用户名|No-密码)",
                                            QMessageBox::Yes | QMessageBox::No | QMessageBox::Cancel);
         if (ret == QMessageBox::Yes ) {
             QString newname = QInputDialog::getText(this, tr("提示"),
                                          tr("修改用户名！"), QLineEdit::Normal,
-                                         tr("请输入要修改的用户名"), &ok);
-
+                                         tr(""), &ok);
+            if (newname.isEmpty()) {
+                QMessageBox::warning(this,"提示","输入为空",QMessageBox::Ok);
+                return;
+            }
             QString str = QString("UPDATE user SET username = '%1' WHERE username = '%2'").arg(newname).arg(text);
             QSqlQuery sql_query(db);
             if (!sql_query.exec(str)) {
@@ -130,7 +145,10 @@ void UserWindow::on_updata_usr_clicked()
             QString newpassword = QInputDialog::getText(this, tr("提示"),
                                          tr("修改密码"), QLineEdit::Normal,
                                          tr("请输入需要修改的密码"), &ok);
-
+            if (newpassword.isEmpty()) {
+                QMessageBox::warning(this,"提示","输入为空",QMessageBox::Ok);
+                return;
+            }
             QString str = QString("UPDATE user SET password = '%1' WHERE username = '%2'").arg(newpassword).arg(text);
             QSqlQuery sql_query(db);
             if (!sql_query.exec(str)) {