窗體間的傳值勇吊,最好使用委托方式傳值曼追,開(kāi)始之前,我們先來(lái)說(shuō)一下委托與事件的關(guān)系萧福。
委托:是一個(gè)?類?拉鹃。
事件:是?委托類型?的一個(gè)?特殊實(shí)例?,只能在?類?的?內(nèi)部觸發(fā)執(zhí)行?鲫忍。
首先創(chuàng)建2個(gè)窗體膏燕,這里我們以form1為發(fā)送窗體,form2為接收窗體
form1窗體
form2窗體
方式一(?最簡(jiǎn)單的方式?)
form1窗體代碼
usingSystem;usingSystem.Collections.Generic;usingSystem.ComponentModel;usingSystem.Data;usingSystem.Drawing;usingSystem.Linq;usingSystem.Text;usingSystem.Threading.Tasks;usingSystem.Windows.Forms;namespace事件的方式實(shí)現(xiàn)窗體間傳值{publicpartialclassForm1 : Form? ? {publicForm1(){? ? ? ? ? ? InitializeComponent();? ? ? ? }publicForm2 msgFrm { get;set; }privatevoidForm1_Load(object sender, EventArgs e){? ? ? ? ? ? Form2 f2 =newForm2();? ? ? ? ? ? msgFrm = f2;? ? ? ? ? ? f2.Show();? ? ? ? }privatevoidbtnSendMsg_Click(object sender, EventArgs e){//對(duì)象內(nèi)部的悟民,字段或者元素屬性最好不要直接讓外部直接訪問(wèn)//最好是通過(guò)坝辫,設(shè)置的方法來(lái)控制一下msgFrm.SetTxt(this.txtMsg.Text);? ? ? ? ? ? ? ? ? ? }? ? }}
form2窗體代碼
1usingSystem;2usingSystem.Collections.Generic;3usingSystem.ComponentModel;4usingSystem.Data;5usingSystem.Drawing;6usingSystem.Linq;7usingSystem.Text;8usingSystem.Threading.Tasks;9usingSystem.Windows.Forms;1011namespace事件的方式實(shí)現(xiàn)窗體間傳值12{13publicpartialclassForm2 : Form14{15publicForm2()16{17InitializeComponent();18}19publicvoidSetTxt(stringtxt)20{21this.txtMsg.Text = txt;22}23}24}
方式二(?委托方式?)
注:委托不熟悉的寶寶們,請(qǐng)自行查閱Func與Action射亏,以及delegate三者區(qū)別近忙,這里我們用系統(tǒng)?內(nèi)置?的?委托Action
form1窗體代碼
1usingSystem;2usingSystem.Collections.Generic;3usingSystem.ComponentModel;4usingSystem.Data;5usingSystem.Drawing;6usingSystem.Linq;7usingSystem.Text;8usingSystem.Threading.Tasks;9usingSystem.Windows.Forms;101112namespace事件的方式實(shí)現(xiàn)窗體間傳值13{14publicpartialclassForm1 : Form15{16publicForm1()17{18InitializeComponent();19}20//定義委托21publicAction afterMsgSend { get;set; }22privatevoidForm1_Load(object sender, EventArgs e)23{24Form2 f2 =newForm2();25afterMsgSend += f2.SetTxt;//給系統(tǒng)內(nèi)置的委托注冊(cè)事件26f2.Show();27}2829privatevoidbtnSendMsg_Click(object sender, EventArgs e)30{31if(afterMsgSend == null)32{33return;34}35afterMsgSend(this.txtMsg.Text);36}37}38}
form2窗體代碼
1usingSystem;2usingSystem.Collections.Generic;3usingSystem.ComponentModel;4usingSystem.Data;5usingSystem.Drawing;6usingSystem.Linq;7usingSystem.Text;8usingSystem.Threading.Tasks;9usingSystem.Windows.Forms;1011namespace事件的方式實(shí)現(xiàn)窗體間傳值12{13publicpartialclassForm2 : Form14{15publicForm2()16{17InitializeComponent();18}19publicvoidSetTxt(stringtxt)20{21this.txtMsg.Text = txt;22}23}24}
方式三(?事件方式,更安全喲?)
TextBoxMsgChangeEventArg?類繼承?EventArgs?代碼
1usingSystem;2usingSystem.Collections.Generic;3usingSystem.Linq;4usingSystem.Text;5usingSystem.Threading.Tasks;67namespace事件的方式實(shí)現(xiàn)窗體間傳值8{9publicclassTextBoxMsgChangeEventArg:EventArgs10{11publicstringText { get;set; }12}13}
form1窗體代碼
1usingSystem;2usingSystem.Collections.Generic;3usingSystem.ComponentModel;4usingSystem.Data;5usingSystem.Drawing;6usingSystem.Linq;7usingSystem.Text;8usingSystem.Threading.Tasks;9usingSystem.Windows.Forms;101112namespace事件的方式實(shí)現(xiàn)窗體間傳值13{14publicpartialclassForm1 : Form15{16publicForm1()17{18InitializeComponent();19}20publicevent EventHandler AfterMsgChange;21privatevoidForm1_Load(object sender, EventArgs e)22{23Form2 f2 =newForm2();24AfterMsgChange += f2.AfterTxtChange;25f2.Show();26}27privatevoidbtnSendMsg_Click(object sender, EventArgs e)28{29AfterMsgChange(this,newTextBoxMsgChangeEventArg() { Text =this.txtMsg.Text });30}31}32}
form2窗體
1usingSystem;2usingSystem.Collections.Generic;3usingSystem.ComponentModel;4usingSystem.Data;5usingSystem.Drawing;6usingSystem.Linq;7usingSystem.Text;8usingSystem.Threading.Tasks;9usingSystem.Windows.Forms;1011namespace事件的方式實(shí)現(xiàn)窗體間傳值12{13publicpartialclassForm2 : Form14{15publicForm2()16{17InitializeComponent();18}19publicvoidAfterTxtChange(object sender,EventArgs e)20{21//拿到父窗體傳來(lái)的文本智润,強(qiáng)轉(zhuǎn)數(shù)據(jù)類型22TextBoxMsgChangeEventArg arg = e as TextBoxMsgChangeEventArg;23this.SetTxt(arg.Text);24}25}26}
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