Detailed usage of CheckBoxList check box list control in ASP. NET

You can use two types of ASP. NET controls to add check boxes to an Web form page: a separate CheckBox control or an CheckBoxList control. Both controls provide a way for users to enter Boolean data (true or false, yes or no).

This article mainly introduces CheckBoxList. It goes without saying that List is a list (collection), and a control can contain multiple CheckBox. Let's take a look at the specific usage below.

1. Bind data

this.lngCatalogID.DataSource = dt; // Here I'm tied to DataTable Here we go .

this.lngCatalogID.DataTextField = "strCatalogName"; // The value seen by the foreground , That is CheckBoxList The value displayed in the 

this.lngCatalogID.DataValueField = "lngCatalogID"; // This value is not visible directly on the page , But you can see it in the source code 

this.lngCatalogID.DataBind();

2. Get the checked item

foreach(ListItem li in lngCatalogID.Items)

{

    if(li.Selected)    // Indicates a 1 Item is selected 

    {   

        //li.Test Indicates the value seen , Corresponding to the above strCatalogName

        //li.Value Represents the value corresponding to the value seen . Corresponding to the above lngCatalogID

    }

}

3. Set an item to be checked

foreach(ListItem li in lngCatalogID.Items)

{

    if(li.Value.Equals(" Hook condition "))    // If li.Value Value is equal to a value , Just tick 

    {

        li.Selected = true;                    // Equal to true It means it is checked .

        break;

    }

}

4. All selections in DataGrid

foreach(DataGridItem thisItem in DataGridLogininfo.Items)

{

    ((CheckBox)thisItem.Cells[0].Controls[1]).Checked = CheckBox2.Checked;

}

Step 5 Reverse selection

for (int i = 0; i < checkedListBox1.Items.Count; i++)

{

    if (checkedListBox1.GetItemChecked(i))

    {

        checkedListBox1.SetItemChecked(i, false);

    }

    else

    {

        checkedListBox1.SetItemChecked(i, true);

    }

}

Example Usage of CheckBoxList Control

Example 1. Loop through each option, containing the setting of the corresponding value to the selected state

for (int i = 0; i < hfAnswers.Value.Split(',').Length; i++)// To CheckBoxList Selected check box   Assignment 

{

    for (int j = 0; j < CBoxListAnswer.Items.Count; j++)

    {

        if (hfAnswers.Value.Split(',')[i] == CBoxListAnswer.Items[j].Value)

        {

          CBoxListAnswer.Items[j].Selected = true;

        }

    }

}

Example 2. Loop through each option, splicing the value of the selected option into a string for subsequent insertion into the database

string m_strTemp = string.Empty;

for (int i = 0; i < CBoxListAnswer.Items.Count; i++)// Read CheckBoxList  Selected value , Preserve 

{

    if (CBoxListAnswer.Items[i].Selected)

    {

        m_strTemp += CBoxListAnswer.Items[i].Value + ",";

    }

}

if (!string.IsNullOrEmpty(m_strTemp))

    Label1.Text = m_strTemp.Substring(0, m_strTemp.Length - 1);

else

    Label1.Text = m_strTemp;