開始的時候按鈕事件中，可能寫的是這樣一段代碼：

if (isexpand) {

[lblbrief setnumberoflines:2];

lblbrief.text = [stringutil substring:strbrief andsublength:90];

[btnbrief setimage:[uiimage imagenamed:@detailbriefdown] forstate:uicontrolstatenormal];

[btnbrief setimage:[uiimage imagenamed:@detailbriefdown] forstate:uicontrolstatehighlighted];

}else{

[lblbrief setnumberoflines:0];

lblbrief.text = strbrief;

[btnbrief setimage:[uiimage imagenamed:@detailbriefup] forstate:uicontrolstatenormal];

[btnbrief setimage:[uiimage imagenamed:@detailbriefup] forstate:uicontrolstatehighlighted];

}

可以通過setnumberoflines:0,來讓概述的所以內容顯示出來，但如果，不計算所要顯示全部內容的總高度，label的寬高是不會自動增大的。

else{

[lblbrief setnumberoflines:0];

lblbrief.text = strbrief;

cgsize constraint = cgsizemake(self.view.frame.size.width - (15 * 2), 20000.0f);

cgsize size = [strbrief sizewithfont:[uifont systemfontofsize:10]constrainedtosize:constraint linebreakmode:uilinebreakmodewordwrap];

[brief setframe:cgrectmake(15,160,size.width,size.height)];

[btnbrief setimage:[uiimage imagenamed:@detailbriefup]forstate:uicontrolstatenormal];

[btnbrief setimage:[uiimage imagenamed:@detailbriefup]forstate:uicontrolstatehighlighted];

}

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