循环访问表单上的一些控件

Question

使用 c# win 表单

我有一个包含许多文本框和组合框的表单

部分控件 - 不是全部 - 不能为空

如果用户单击保存按钮，我希望该空控件的标签变为红色....

我试过了

if (cmbNyaba.SelectedIndex == -1)
        {
            lblNyaba.ForeColor = Color.Red;
            return;
        }
        else
        {
            lblNyaba.ForeColor = Color.Black;
        }


if (txtCaseHasr.Text == "")
        {
            lblHasrNum.ForeColor = Color.Red;
            return;
        }
        else
        {
            lblHasrNum.ForeColor = Color.Black;
        }


if (txtCaseNum.Text == "")
        {
            lblCaseNum.ForeColor = Color.Red;
            return;
        }
        else
        {
            lblCaseNum.ForeColor = Color.Black;
        }

但我认为这不是一个好方法

我应该使用标签属性还是什么？

谢谢

我试过了

public static Boolean ValidateControle(Control MyObjet, int oblig = 0)
    {
        ErrorProvider err = new ErrorProvider();

        String mess = "";
        Boolean valid = true;
        if (MyObjet != null)
        {

            if (oblig == 1)
            {

                mess = "Can not be empty !";
            }

            if (MyObjet.Text.Trim().Length == 0) valid = false;

            if (MyObjet is ComboBox)
            {
                ComboBox cmb = (MyObjet as ComboBox);
                if (cmb.SelectedIndex == -1)
                {
                    mess = "Select at least one element !";
                    valid = false;
                }
            }
            if (valid == false)
            {
                err.SetError(MyObjet, mess);
                MyObjet.BackColor = Color.FromArgb(253, 108, 119);
            }
            else
            {                   
                err.SetError(MyObjet, "");
                MyObjet.BackColor = Color.White;
            }

            err.SetIconAlignment(MyObjet, ErrorIconAlignment.MiddleRight);
        }    
        return valid;          
    }


private void btnSave_Click(object sender, EventArgs e)
    {


        if (cmbCaseCrime.SelectedIndex == -1 || 
           cmbMember.SelectedIndex == -1 ||
           cmbCaseType.SelectedIndex == -1 ||
           string.IsNullOrEmpty(txtCaseNum.Text) ||
           string.IsNullOrEmpty(txtCaseHasr.Text))
        {
            ValidateControle(cmbCaseCrime, 1);
            ValidateControle(cmbMember, 1);
            ValidateControle(cmbCaseType, 1);
            ValidateControle(txtCaseHasr, 1);
            ValidateControle(txtCaseNum, 1);

            return;
        }

        string str = btnSave.Text;
        switch (str)
        {
            case "add":

                DataTable dt = new DataTable();
                dt = cs.Verify_CASES(txtCaseNum.Text, txtCaseYear.Text, Convert.ToInt32(cmbCaseType.SelectedValue), Convert.ToInt32(cmbCaseRegion.SelectedValue));
                if (dt.Rows.Count > 0)
                {
                    MessageBox.Show("already added ", "", MessageBoxButtons.OK, MessageBoxIcon.Error);
                    return;
                }
                else
                {
                    ce.ADD_CASE(txtCaseNum.Text, txtCaseHasr.Text, dtp_CaseComingDate.Value, txtCaseYear.Text,
                            Convert.ToInt32(cmbCaseType.SelectedValue),
                            Convert.ToInt32(cmbCaseRegion.SelectedValue),
                            Convert.ToInt32(cmbCaseStatus.SelectedValue),
                            Convert.ToInt32(cmbCaseCrime.SelectedValue),
                            Convert.ToInt32(cmbMember.SelectedValue), txtCaseStatusDate.Text);



                    MessageBox.Show("added successfuly", " ", MessageBoxButtons.OK, MessageBoxIcon.Information);

                    this.txtidCase.Text = ce.GET_LAST_CASE_ID().Rows[0][0].ToString();

                    this.btnAddRemain.Enabled = true;
                    this.cmbCaseRemain.Focus();
                    this.btnSave.Enabled = false;


                }

Answer 1

您可以做的第一件事是使用 this.Controls.OfType<T> 查找给定类型的所有控件。例如，查找哪些标签为空可能类似于

var labels = this.Controls.OfType<Label>();
foreach(var label in labels)
if(label.Text == "")
//the actions you want to do.

不过，如果您有一些容器控件，则还必须遍历它们。

您可以尝试的第二种方法是使用 Validating 和 Validated 事件。

Answer 2

你可以使用这个功能:

    public static Boolean ValidateControle(Control MyObjet, int oblig=0)
    {
        ErrorProvider err=new ErrorProvider ();

        String mess = "";
        Boolean valid = true;
        if (MyObjet != null)
        {

            if (oblig == 1)
            {

                mess = "Can not be empty !";
            }

            if (MyObjet.Text.Trim().Length == 0) valid = false;


            if (MyObjet is ComboBox)
            {
                ComboBox cmb = (MyObjet as ComboBox);
                if (cmb.SelectedIndex == -1)
                {
                    mess = "Select at least one element !";
                    valid = false;
                }
            }


            if (valid == false)
            {
                err.SetError(MyObjet, mess);
                MyObjet.BackColor = Color.FromArgb(253, 108, 119);

            }
            else
            {
                err.SetError(MyObjet, "");
                MyObjet.BackColor = Color.White;
            }

            err.SetIconAlignment(MyObjet, ErrorIconAlignment.BottomRight);
        }
        return valid;
    }

并且您可以使用 oblig 参数来指定控件是否可以为空。在此调用中，您可以通过在第二个参数中传递 1 来指定控件是必需的通过 :

调用函数

 ValidateControle(textBox1, 1);

   ValidateControle(comboBox1,1);
     ValidateControle(comboBox2,0);

或：

 foreach ( Control cn in this.Controls )
            {
                ValidateControle(cn);

            }

Answer 3

为此，您必须在 class 中声明您的提供商，例如：

 public partial class Form1 : Form

{
    ErrorProvider err = new ErrorProvider();

    public Form1()
    {
        InitializeComponent();
    }

对于测试你是否必须记录你可以这样做：

 private void button3_Click(object sender, EventArgs e)
        {
           bool test  =true  ;

            test= ValidateControle(textBox1, 1);

           test= ValidateControle(comboBox1,1);

           if (test)
           {
               //continue working and saving the record
           }
           else
           {
               //Stop and traancate recording

           }

        }

要清除所有错误标志，您可以将 void 声明为：

private void ClearError()       
        {

            foreach (Control cn in this.Controls)
            {

                err.SetError(cn,"");

                err.Clear();
                cn.BackColor = Color.White;

            }
        }

如果你想要清除错误标志，你可以调用这个函数。如果我的回答对您有帮助，请点赞并标记为已解决

Answer 4

首先，您必须在 class 形式下将 ErrorProvider 声明为全局，并添加一个 void ClearError as :

     public partial class Form1 : Form
        {
            ErrorProvider err = new ErrorProvider();

            public Form1()
            {
                InitializeComponent();
            }

            private void Form1_Load(object sender, EventArgs e)
            {

            }
  private void ClearError()       
        {

           // ErrorProvider err = new ErrorProvider();

            foreach (Control cn in this.Controls)
            {

                err.SetError(cn,"");

                err.Clear();
                cn.BackColor = Color.White;

            }
        }

并且您必须将 btnSave_Click 更改为 :

private void btnSave_Click(object sender, EventArgs e)
{

        bool test =true ;
    ClearError (); // for clear all mark error in all conrols in the form
     test=   ValidateControle(cmbCaseCrime, 1);
      test=  ValidateControle(cmbMember, 1);
      test=  ValidateControle(cmbCaseType, 1);
       test= ValidateControle(txtCaseHasr, 1);
      test=  ValidateControle(txtCaseNum, 1);

        if (test ==false )
        {
            MessageBox .Show("You have some error !");
        return;
        }

    string str = btnSave.Text;
    switch (str)
    {
        case "add":

            DataTable dt = new DataTable();
            dt = cs.Verify_CASES(txtCaseNum.Text, txtCaseYear.Text, Convert.ToInt32(cmbCaseType.SelectedValue), Convert.ToInt32(cmbCaseRegion.SelectedValue));
            if (dt.Rows.Count > 0)
            {
                MessageBox.Show("already added ", "", MessageBoxButtons.OK, MessageBoxIcon.Error);
                return;
            }
            else
            {
                ce.ADD_CASE(txtCaseNum.Text, txtCaseHasr.Text, dtp_CaseComingDate.Value, txtCaseYear.Text,
                        Convert.ToInt32(cmbCaseType.SelectedValue),
                        Convert.ToInt32(cmbCaseRegion.SelectedValue),
                        Convert.ToInt32(cmbCaseStatus.SelectedValue),
                        Convert.ToInt32(cmbCaseCrime.SelectedValue),
                        Convert.ToInt32(cmbMember.SelectedValue), txtCaseStatusDate.Text);



                MessageBox.Show("added successfuly", " ", MessageBoxButtons.OK, MessageBoxIcon.Information);

                this.txtidCase.Text = ce.GET_LAST_CASE_ID().Rows[0][0].ToString();

                this.btnAddRemain.Enabled = true;
                this.cmbCaseRemain.Focus();
                this.btnSave.Enabled = false;


            }

希望能解决您的问题，请为答案投票并将其标记为已解决。

循环访问表单上的一些控件

loop through some controls on a form

c#

combobox

textbox

winforms