ls_Ret = dw_1.describe("DataWindow.Header.Height")
IF ls_Ret = '' OR ls_Ret = '!' THEN ls_Ret = 'FALSE'
请问什么情况下返回 ！ 感叹号,
返回值有几种情况
------解决方案--------------------
If the property list contains an invalid item, Describe returns an exclamation point (!) for that item and ignores the rest of the property list. Describe returns a question mark (?) if there is no value for a property.
1. 返回字符串
2. 返回 ！
3. 返回 ？
4. 返回 Null
完整返回值定义 ： 参考资料 pb F1
Return value
Returns a string that includes a value for each property or Evaluate function. A newline character (~n or \n) separates the value of each item in propertylist.
If the property list contains an invalid item, Describe returns an exclamation point (!) for that item and ignores the rest of the property list. Describe returns a question mark (?) if there is no value for a property.
When the value of a property contains an exclamation point or a question mark, the value is returned in quotes so that you can distinguish between the returned value and an invalid item or a property with no value.
If any argument's value is NULL, in PowerBuilder and JavaScript the method returns NULL.
------解决方案--------------------
如果指定的字段值无效就会返回!号，比如字段不存在之类的;
如果属性值未设置就会返回?号，比如tag的值，若未设置时就会返回?号
如果describe内部的参数值为null,返回值就会为null
------解决方案--------------------
楼上中文解释真好。呵呵，我最头疼英文。