先看一大段测试代码，每个小方法的注释行是输出结果。
private var text_content:TextField;
private function textFieldDemo():void{
text_content=new
TextField();
addChild(text_content);
textFieldDemo26();
}
private function
textFieldDemo1():void{
trace(text_content.width);
text_content.text="nihao";
trace(text_content.width);
text_content.autoSize="left";
trace(text_content.width);
//text正常显示，输出100
100 30
}
private function
textFieldDemo12():void{
text_content.multiline=true;
trace(text_content.width);
text_content.text="nihao";
trace(text_content.width);
text_content.autoSize="left";
trace(text_content.width);
//text正常显示，输出100
100 30
}
private function
textFieldDemo13():void{
text_content.wordWrap=true;
trace(text_content.width);
text_content.text="nihao";
trace(text_content.width);
text_content.autoSize="left";
trace(text_content.width);
//text正常显示，输出100
100 100
}
private function
textFieldDemo14():void{
trace(text_content.width);
text_content.text="nihao";
trace(text_content.width);
text_content.autoSize="left";
trace(text_content.width);
text_content.wordWrap=true;
trace(text_content.width);
//text正常显示，输出100
100 30 30
}
private function
textFieldDemo15():void{
text_content.width=222;
text_content.wordWrap=true;
trace(text_content.width);
text_content.text="nihao";
trace(text_content.width);
text_content.autoSize="left";
trace(text_content.width);
//text正常显示，输出222
222 222
}
private function
textFieldDemo16():void{
text_content.text="nihao";
trace(text_content.width);
text_content.wordWrap=true;
trace(text_content.width);
text_content.autoSize="left";
trace(text_content.width);
//text正常显示，输出100
100 100
}
private function
textFieldDemo2():void{
trace(text_content.width);
text_content.autoSize="left";
trace(text_content.width);
text_content.text="nihao";
trace(text_content.width);
//text正常显示，输出100
4 30
}
private function
textFieldDemo22():void{
text_content.multiline=true;
trace(text_content.width);
text_content.autoSize="left";
trace(text_content.width);
text_content.text="nihao";
trace(text_content.width);
//text正常显示，输出100
4 30
}
private function
textFieldDemo23():void{
text_content.wordWrap=true;
trace(text_content.width);
text_content.autoSize="left";
trace(text_content.width);
text_content.text="nihao";
trace(text_content.width);
//text正常显示，输出100
100 100
}
private function
textFieldDemo24():void{
trace(text_content.width);
text_content.autoSize="left";
trace(text_content.width);
text_content.text="nihao";
trace(text_content.width);
text_content.wordWrap=true;
trace(text_content.width);
//text正常显示，输出100
4 30 30
}
private function
textFieldDemo25():void{
text_content.width=222;
text_content.wordWrap=true;
trace(text_content.width);
text_content.autoSize="left";
trace(text_content.width);
text_content.text="nihao";
trace(text_content.width);
//text正常显示，输出222
222 222
}
private function
textFieldDemo26():void{
text_content.width=222;
text_content.autoSize="left";
trace(text_content.width);
text_content.wordWrap=true;
trace(text_content.width);
text_content.text="nihao";
trace(text_content.width);
//text"不显示"(界面上看不到textfield)，输出4
4 4
}
仔细分析上面的代码执行结果，可以得出如下结论：
1.设置wordwrap,mulitline不会导致width值发生变化，但设置wordwrap可能会对width的值产生影响。
2.设置autosize属性，当wordwrap为false时导致width值发生变化，当wordwrap为true时不对width产生影响。
3.设置text属性，当wordwrap为false并且autosize不为none时，width值才发生变化。否则不对width产生影响。
就是说，wordwrap autosize text对width都有决定作用。
神奇的TextField(1),布布扣,bubuko.com
原文：http://www.cnblogs.com/tianlanliao/p/3671882.html