iOS Webview 实现修改javascript confirm 和 alert

@interface UIWebView (JavaScriptAlert)
-(void) webView:(UIWebView *)sender runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(id)frame;
- (BOOL)webView:(UIWebView *)sender runJavaScriptConfirmPanelWithMessage:(NSString *)message initiatedByFrame:(id)frame;
@end

@implementation UIWebView (JavaScriptAlert)

- (void)webView:(UIWebView *)sender runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(id)frame {
UIAlertView* customAlert = [[UIAlertView alloc] initWithTitle:@"助手提示" message:message delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil];
[customAlert show];
}
static BOOL diagStat = NO;
static NSInteger bIdx = -1;
- (BOOL)webView:(UIWebView *)sender runJavaScriptConfirmPanelWithMessage:(NSString *)message initiatedByFrame:(id)frame {
UIAlertView *confirmDiag = [[UIAlertView alloc] initWithTitle:@"助手提示"
message:message
delegate:self
cancelButtonTitle:@"取消"
otherButtonTitles:@"确定", nil];

[confirmDiag show];
bIdx = -1;

while (bIdx==-1) {
//[NSThread sleepForTimeInterval:0.2];
[[NSRunLoop mainRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:0.1f]];
}
if (bIdx == 0){//取消;
diagStat = NO;
}
else if (bIdx == 1) {//确定;
diagStat = YES;
}
return diagStat;
}

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
bIdx = buttonIndex;
}

@end