Question

如何获取combobox选中的值

Answer 1

1.添加combobox后做如下设置

2.根据自己的需要在类中重写如下方法

// ==========================================================
// Combo box data source methods
// ==========================================================
- (NSInteger) numberOfItemsInComboBox: (NSComboBox *) aComboBox {
#pragma unused (aComboBox)
return ([dataSource count]);
}
- (id) comboBox: (NSComboBox *) aComboBox objectValueForItemAtIndex: (NSInteger) index {
#pragma unused (aComboBox)
return [dataSource objectAtIndex:index];
}
- (NSUInteger) comboBox: (NSComboBox *) aComboBox indexOfItemWithStringValue: (NSString *) string {
#pragma unused (aComboBox)
return [dataSource indexOfObject:string];
}

- (NSString *) firstGenreMatchingPrefix: (NSString *) prefix {
NSString *string = nil;
NSString *lowercasePrefix = [prefix lowercaseString];
NSEnumerator *stringEnum = [dataSource objectEnumerator];

while ( string = [stringEnum nextObject] )
if ([[string lowercaseString] hasPrefix:lowercasePrefix] ) {
return (string) ;
}

return (nil);
} // firstGenreMatchingPrefix

- (NSString *) comboBox: (NSComboBox *) aComboBox completedString: (NSString *) inputString {
#pragma unused (aComboBox)
// This method is received after each character typed by the user, because we have checked the "completes" flag for
// genreComboBox in IB.
// Given the inputString the user has typed, see if we can find a genre with the prefix, and return it as the suggested complete
// string.
NSString *candidate = [self firstGenreMatchingPrefix:inputString];
return (candidate ? candidate : inputString);
}
这些方法实现combobox在选择选项、自动完成时的处理方式。其中dataSource为NSArray。
3.设置combobox的datasource为实现上述方法的对象即可。

Answer 2

string bianlian; //定义一个string 类型的变量
bianlian=combobox.selecteditem.text ;把下拉列表框中的值读出赋给变量名bianliang

Answer 3

• using System;  

• using System.Collections.Generic;  

• using System.ComponentModel;  

• using System.Data;  

• using System.Drawing;  

• using System.Linq;  

• using System.Text;  

• using System.Threading.Tasks;  

• using System.Windows.Forms;  

• namespace WindowsFormsApplication1  

• {  

• public partial class Form1 : Form  

• {  

• public Form1()  

• {  

• InitializeComponent();  

• }  

• private void Form1_Load(object sender, EventArgs e)  

• {  

• //添加数据项  

• comboBox1.Items.Add("apple");  

• comboBox1.Items.Add("banana");  

• }  

• private void button1_Click(object sender, EventArgs e)  

• {  

• MessageBox.Show(comboBox1.SelectedItem.ToString());  

• }  

• }  

• }